Urban forests are integral to human health and well-being and are a vital component of healthy, thriving cityscapes.
We analysed the data on over 5 million trees spread across 63 major US cities to assess the diversity and distribution of tree species in urban forests across the US.
The top ten and fifty most frequently observed trees were identified for each city, as were local tree-planting initiatives aimed at increasing canopy cover.
Species diversity is essential for the ecological health and resilience of urban forests. In this analysis, the number of unique species and the effective number of species (ENS) was calculated for each city to gain insights into the diversity of each urban forest.
ENS is a valuable indicator of the richness and evenness of the local tree population and was derived using the Shannon Diversity Index.
The following charts and graphs provide valuable insights into the distribution and diversity of species in urban forests across the US.
Key Takeaways
- Urban forests play a critical role in human health and well-being. ↓
- Tree cover in urban areas has declined in recent years while impervious cover has increased.↓
- A dynamic management approach to urban forests is required as urban areas increase in size.↓
- Government regulations, incentives, and initiatives can influence the private management and planting of urban trees.↓
- Diversity among tree species is essential for the health and stability of urban forests.↓
- Low species diversity makes the urban forest more vulnerable to environmental challenges, pests, and diseases that may impact the dominant species.↓
- Across 63 US cities and census-designated places, the London planetree (Platanus acerifolia) was observed in the highest numbers.↓
- The median effective number of species across the analyzed cities was found to be 34.53. This means that, in most cities, tree diversity is equivalent to having 35 distinct species, each represented in equal numbers.↓
- The city with the highest diversity score was Seattle, WA, with an effective number of species count of 108.81.↓
- The city with the lowest diversity score was Worcester, MA, with an effective number of species count of 6.43.↓
Common Trees in 63 Urban Forests Across the United States
An urban forest is a collection of trees growing within an urban area. Due to their close proximity to human populations, urban forests play an integral role in human health and well-being.
By helping to mitigate issues associated with increasing urbanization, urban forests improve air quality, assist temperature regulation, reduce flooding risk by managing stormwater runoff, act as natural sound barriers, and positively impact people’s health and mental well-being.
The United States is home to an estimated 5.5 billion urban trees1 but tree cover in urban areas has declined in recent years at a rate of about 36 million trees per year, while impervious cover (such as roads and buildings) has increased2.
This trend will likely continue without a change in development and management practices.
Urban land in the conterminous United States is projected to increase from 3.6% (67.6 million acres) in 2010 to 8.6% (163.1 million acres) in 20601, further highlighting the need for a dynamic management approach to urban forests.
Within urban forests, trees are managed both privately (by individual landowners) and publicly, but government regulations, incentives, and initiatives can help influence private management.
Control of invasive species, pests, and diseases is necessary to help sustain urban forest integrity and to reduce the spread of such issues into rural forests as urban areas continue to expand.
Many states and cities already have tree-planting initiatives in place to increase urban canopy cover, increase species diversity and improve the sustainability of their urban forests.
We analyzed the data on 5,182,022 trees in 63 US cities and census-designated places (CDPs)3 to see which were the most common and provide insights into the current state of urban forest diversity within the US.
Here are the results!
- Number of Cities Included: 63
- Total Number of Trees Observed: 5,182,022
- Median Number of Trees: 41,250
- Median Unique Species: 153
- Median Effective Species: 34.53
Top 10 Common Trees Observed Across 63 US Cities
- London planetree (Platanus acerifolia) – 4.20%
- Crape myrtle (Lagerstroemia indica) – 4.06%
- Norway maple (Acer platanoides) – 4.04%
- Honeylocust (Gleditsia triacanthos) – 3.20%
- Callery pear (Pyrus calleryana) – 3.09%
- Green ash (Fraxinus pennsylvanica) – 3.01%
- Red maple (Acer rubrum) – 2.71%
- American sweetgum (Liquidambar styraciflua) – 2.15%
- Littleleaf linden (Tilia cordata) – 2.06%
- Live oak (Quercus virginiana) – 2.01%
* All other species combined comprise 69.48% of the total tree population analyzed.
** The common name used is the one most frequently associated with each scientific name across all cities in the dataset.
Tree Diversity in US Urban Forest Areas
In addition to extracting data on the most common trees for each of the 63 cities and census-designated places in this analysis, the number of unique species was identified, and the effective number of species was calculated.
Although the ability to make direct comparisons is limited by the different sample sizes and data collection processes used in each city’s dataset, these figures can provide essential insights into species diversity among urban forests.
This histogram displays the frequency distribution of the total number of trees analyzed in each city. The red dashed line represents the median value of 41,250.
This histogram shows the frequency distribution of the unique species found across the cities. The red dashed line represents the median value of 153.
This histogram represents the distribution of effective species numbers across the cities. The red dashed line represents the median value of 34.53
Further insights into the state of tree diversity in the US can be gained by analyzing the common trees, number of unique species, and effective species number in each city.
Most Common Tree Types Observed in 63 US Cities
List of US Cities Analyzed
Common Trees in Albuquerque, New Mexico
As the largest city in the state of New Mexico with a population of approximately 560,000, Albuquerque ranks as the 32nd most populated city in the USA.
Albuquerque is committed to enhancing livability and air quality by expanding its urban tree cover and has various initiatives to achieve this goal. One initiative includes planting 100,000 new trees in the city by 2030.
We analyzed the data on 2,502 trees currently growing in the city to determine which species are found most commonly in Albuquerque, NM, and how diverse the city’s urban forest is.
Here are the results:
Top 10 Most Common Trees Observed in Albuquerque, NM
- Siberian elm (Ulmus pumila): 8.63%
- London plane (Platanus acerifolia): 7.43%
- Honeylocust (Gleditsia triacanthos): 6.35%
- Austrian pine (Pinus nigra): 5.96%
- Ash (Fraxinus): 5.92%
- Crabapple (Malus): 5.08%
- Chinese elm (Ulmus parvifolia): 3.28%
- Texas red oak (Quercus buckleyi): 2.92%
- Elm hybrid (Ulmus): 2.72%
- Desert willow (Chilopsis linearis): 2.52%
* All other species combined comprise 49.20% of the total tree population analyzed.
Tree Diversity in Albuquerque, NM
With 94 unique tree species observed in this analysis and an effective species number of 39.44, Albuquerque has a reasonably diverse urban forest, akin to having 39 different species in equal numbers.
The city’s urban forest comprises a mix of introduced (non-native) species with fewer native trees.
The dominant species observed was the introduced Siberian elm (Ulmus pumila) which accounts for 8.63% of the total tree population. Other common tree species observed in Albuquerque include the London plane (Platanus acerifolia) and Honeylocust (Gleditsia triacanthos), both non-native species.
The careful selection and planting of additional native species may serve to enhance the ecological stability of Albuquerque’s urban forest while fostering a closer link to local ecosystems.
Common Trees in Anaheim, California
Best recognized as the home of Disneyland Resort, Anaheim, CA, is a vibrant city with a population of approximately 350,000. However, the city’s tourist appeal continues beyond theme parks!
The City of Anaheim is committed to preserving its natural beauty and urban tree cover. Residents and businesses are encouraged to get involved in the TreePower Program by receiving up to 6 free trees to plant around their homes. The program includes consultation with a TreePower representative to help the homeowner select the best types of trees and planting sites.
Initiatives like these will ensure that Anaheim maintains and grows its urban tree cover, creating healthy environments for residents, tourists, and local wildlife.
We analyzed the data on 57,050 trees growing in Anaheim, CA, to see which are the most common species found in the city and how diverse Anaheim’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Anaheim, CA
- Southern magnolia (Magnolia grandiflora) – 8.01%
- Mexican fan palm (Washingtonia robusta) – 7.68%
- Crape myrtle (Lagerstroemia indica) – 5.82%
- Camphor tree (Cinnamomum camphora) – 4.50%
- Canary Island pine (Pinus canariensis) – 4.06%
- Chinese flame tree (Koelreuteria bipinnata) – 3.90%
- Queen palm (Syagrus romanzoffianum) – 2.99%
- Jacaranda (Jacaranda mimosifolia) – 2.94%
- Brisbane box (Lophostemon confertus) – 2.82%
- American sweetgum (Liquidambar styraciflua) – 2.51%
* All other species combined comprise 54.77% of the total tree population analyzed.
Tree Diversity in Anaheim, CA
Anaheim boasts 328 unique tree species, as observed in this dataset, with an effective species number of 47.56. This means that tree diversity in Anaheim is akin to having 48 equally common species.
Southern magnolia (Magnolia grandiflora) accounts for 8.01% of the total observed tree population, outnumbering other species. Mexican fan palm (Washingtonia robusta) and Crape myrtle (Lagerstroemia indica) were among Anaheim’s other most common trees.
The ten most dominant trees account for less than 50% of the total tree population, another positive indicator of a diverse urban forest.
In the dataset, the majority (85%) of the 57,050 trees observed in Anaheim were categorized as introduced (non-native). Increasing the presence of native species in the city’s urban forest will improve species diversity and foster closer connections to local ecosystems in and around Anaheim.
Common Trees in Arlington, Texas
With a population of approximately 400,000, Arlington is the 7th largest city in Texas and is well recognized for its urban tree cover.
The city of Arlington is committed to protecting its existing tree canopy and increasing urban tree planting, specifically targeting heat islands. The Arlington Tree Committee offers residents the opportunity to request a tree be planted near their home.
Arlington has a diverse and widespread urban tree cover and is known as a green oasis in the heart of Texas.
We analyzed the data on 14,673 trees currently growing in Arlington, TX, to find out which tree species can most commonly be seen in Arlington and how diverse the city’s urban forest is.
Here are the results:
Top 10 Most Common Trees Observed in Arlington, TX
- Cedar Elm (Ulmus crassifolia) – 10.70%
- Crepe Myrtle (Lagerstroemia indica) – 8.14%
- Shumard Oak (Quercus shumardii) – 7.76%
- Southern Live Oak (Quercus virginiana) – 7.37%
- Eastern Redbud (Cercis canadensis) – 4.71%
- Chinkapin Oak (Quercus muehlenbergii) – 4.02%
- Chinese Pistache (Pistacia chinensis) – 4.00%
- Bur Oak (Quercus macrocarpa) – 3.97%
- Bald Cypress (Taxodium distichum) – 3.96%
- Post Oak (Quercus stellata) – 3.80%
* All other species combined comprise 41.57% of the total tree population analyzed.
Tree Diversity in Arlington, TX
Within Arlington, 14,673 were observed; of these, 10,611 were categorized as native. This strong presence of native species indicates that the city of Arlington has a strong connection to the local ecosystem. There were 108 unique species of trees identified, and the effective species number was calculated to be 32.47. This means that tree diversity in Arlington is equivalent to having 32 species in equal numbers.
The Cedar Elm (Ulmus crassifolia) was the most dominant species observed in this analysis, accounting for 10.7% of the total tree population. Other commonly observed species include Crepe Myrtle (Lagerstroemia indica), Shumard Oak (Quercus shumardii), and Southern Live Oak (Quercus virginiana), all of which are present in significantly higher numbers than other species observed.
While urban tree cover is reasonably diverse in Arlington, the dominance of a few species indicates a potential for further improving species diversity.
Common Trees Atlanta, Georgia
The vibrant and dynamic city of Atlanta, Georgia, has a population of almost 500,000 and is a major hub for entertainment and business.
The city is well known for its tree cover, earning it the name ‘City in a Forest’! With approximately 47% of the city space covered by trees, Atlanta is committed to not only maintaining its existing urban tree coverage but also to increasing it dramatically.
The One Million Trees Initiative is a combined effort of metro Atlanta city, Trees Atlanta, and regional non-profit organizations aimed at planting and conserving one million trees across metro Atlanta by 2030!
Residents are encouraged to participate by getting involved in both public and private planting projects.
We analyzed 41,250 trees already growing within Atlanta, GA, to discover which are the most common species represented and how diverse Atlanta’s urban forest is.
Here are the results:
Top 10 Most Common Trees Observed in Atlanta, GA
- Eastern Redbud (Cercis canadensis) – 10.44%
- Crape Myrtle (Lagerstroemia) – 7.18%
- Trident Maple (Acer buergerianum) – 4.60%
- Indian Crape Myrtle (Lagerstroemia indica) – 4.19%
- Nuttall Oak (Quercus nuttallii) – 3.67%
- Red Maple (Acer rubrum) – 3.58%
- White Oak (Quercus alba) – 3.54%
- Black Gum (Nyssa sylvatica) – 3.51%
- Flowering Dogwood (Cornus florida) – 3.13%
- American Elm (Ulmus americana) – 2.40%
* All other species combined comprise 53.76% of the total tree population analyzed.
Tree Diversity in Atlanta, GA
Of the 41,250 trees observed in Atlanta, almost 60% were categorized as native, and 303 unique tree species were observed. The effective species number was calculated to be 58.19, which means that tree diversity in Atlanta is equivalent to having 58 species in equal numbers.
The most dominant species observed in Atlanta was the Eastern Redbud (Cercis canadensis), accounting for 10.44% of the total tree population. Other commonly observed species included the Crape Myrtle (Lagerstroemia) and Trident Maple (Acer buergerianum). The top 10 most common tree species account for less than 50% of the total tree population, another positive indicator of tree diversity in Atlanta.
This data demonstrates the rich biodiversity of Atlanta’s urban canopy contributing to the city’s ecological value and aesthetic appeal.
Common Trees in Aurora, Colorado
Situated in the east-central region of Colorado, Aurora is a vibrant city that showcases rich cultural diversity. With an estimated population of over 390,000, it is the third-largest city in Colorado.
The commitment the city has to preserve and maintain its urban tree canopy is seen in its recognition by the Arbor Day Foundation as a “Tree City USA”. The Forestry Division maintains over 35,000 trees and continues to add to that number by planting Free Trees through their Planting a Legacy program.
We analyzed the data on 57,373 trees currently growing in Aurora, CO to see which are the most common species found in the city and how diverse Aurora’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Aurora, CO
- Honeylocust (Gleditsia triacanthos) – 14.62%
- Linden (Tilia spp.) – 10.64%
- Green ash (Fraxinus pennsylvanica) – 9.53%
- Norway maple (Acer platanoides) – 8.04%
- Silver maple (Acer saccharinum) – 5.98%
- Hackberry (Celtis occidentalis) – 4.29%
- Shademaster honeylocust (Gleditsia triacanthos) – 3.30%
- American linden (Tilia americana) – 2.72%
- Austrian pine (Pinus nigra) – 2.64%
- Siberian elm (Ulmus pumila) – 2.31%
* All other species combined comprise 35.92% of the total tree population analyzed.
Tree Diversity in Aurora, CO
Of the 57,658 trees observed in Aurora, CO at least 71% were categorized as introduced species, and only 6.5% were categorized as native (with the remaining 22.5% of the species being uncategorized).
A total of 133 unique species were observed, but the effective species number was only 22.26. This means that tree diversity in Aurora is equivalent to having just 22 species in equal numbers.
Honeylocust (Gleditsia triacanthos) was the dominant species observed, accounting for 14.62% of the total tree population and significantly outnumbering other species. Linden (Tilia spp.), Green ash (Fraxinus pennsylvanica), and Norway maple (Acer platanoides) were among the other most common trees observed in Aurora and the top 10 trees accounted for over 64% of the total tree population.
The dominance of a few tree species, combined with the uneven distribution among species, indicates there is a potential for improving species diversity in Aurora’s urban forest. The lower numbers of native trees observed suggest that the city may benefit from planting more native species.
Common Trees in Austin, Texas
Austin, the capital city of Texas, is renowned for its music scene and cultural diversity. With a population of over 970,000, Austin is now the 10th largest city in the U.S.
Austin is committed to environmental sustainability and this is reflected in its Urban Forest Plan which promotes the ongoing planting of a sustainable mix of trees and vegetation. Residents are eligible for free trees via the Neighborwoods program.
The current urban tree canopy is impressive and helps to combat urban heat island effects and provides beauty, shade, and a habitat for wildlife.
We analyzed the data on 5,976 trees currently growing in Austin, Texas to see which are the most common species found in the city and how diverse the urban forest in Austin is.
Here are the results!
Top 10 Most Common Trees Observed in Austin, TX
- Pecan (Carya illinoinensis): 15.33%
- Cedar elm (Ulmus crassifolia): 13.91%
- Southern live oak (Quercus virginiana): 13.20%
- Crape myrtle (Lagerstroemia indica): 10.19%
- Escarpment live oak (Quercus fusiformis): 9.89%
- Shumard oak (Quercus shumardii): 8.12%
- American elm (Ulmus americana): 3.88%
- Bald cypress (Taxodium distichum): 2.74%
- Sugarberry (Celtis laevigata): 2.73%
- Texas ash (Fraxinus texensis): 1.87%
* All other species combined comprise 18.14% of the total tree population analyzed.
Tree Diversity in Austin, TX
The tree population in Austin, TX has a strong presence of native trees, with at least 77% of the 5,976 trees observed categorized as naturally occurring.
There were 104 unique tree species observed in Austin; however, the effective species number is only 17.71. This means that tree diversity in Austin is akin to having just 18 different tree species in equal numbers. This lack of diversity is also indicated by the fact that the top 10 trees account for 81.86% of the total tree population.
The dominant species observed was the Pecan (Carya illinoinensis), representing 15.33% of the entire population of trees observed in Austin. Other dominant species include Cedar elm (Ulmus crassifolia), Southern live oak (Quercus virginiana), Crape myrtle (Lagerstroemia indica), and Escarpment live oak (Quercus fusiformis). These five species alone account for over 62% of the total tree population.
While the strong presence of native species in Austin is commendable, this data suggests that due to the dominance of a few species and uneven distribution among species, improving tree diversity should be the focus of new plantings in Austin.
Common Trees in Baltimore, Maryland
Baltimore, often referred to as “Charm City,” has a population of approximately 570,000 and is currently the most populated city in Maryland.
Tree Baltimore offers free yard trees and street trees to plant, which is a fantastic initiative. Bluewater Baltimore also gives away 1,000 trees a year to residents.
The urban tree canopy is growing, improving air quality and heat island effects and enhancing the city’s overall aesthetic.
We analyzed the data on 120,842 trees currently growing in Baltimore, MD to see which are the most common species found in the city and how diverse Baltimore’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Baltimore, MD
- Red maple (Acer rubrum) – 10.67%
- Japanese zelkova (Zelkova serrata) – 5.55%
- London planetree (Platanus acerifolia) – 4.99%
- Littleleaf linden (Tilia cordata) – 4.91%
- Cherry/plum (Prunus) – 4.79%
- Callery pear (Pyrus calleryana) – 3.93%
- Norway maple (Acer platanoides) – 3.08%
- Thornless honeylocust (Gleditsia triacanthos) – 2.65%
- Willow oak (Quercus phellos) – 2.48%
- Northern red oak (Quercus rubra) – 2.36%
* All other species combined comprise 54.60% of the total tree population analyzed.
Tree Diversity in Baltimore, MD
Baltimore’s urban forest demonstrates a commendable level of species diversity with a mix of native and non-native trees. There were 329 unique species identified among the 120,824 trees observed, and the effective species number was calculated to be 54.69. This means tree diversity in Baltimore is equivalent to having 55 common species in equal numbers.
The top 10 trees account for less than 50% of the entire tree population observed in Baltimore, and the dominant species (10.67% of the total tree population) is the native Red maple (Acer rubrum). Other dominant species include the Japanese zelkova (Zelkova serrata), London planetree (Platanus acerifolia), and Littleleaf linden (Tilia cordata).
The diversity of Baltimore’s urban canopy contributes to both the visual appeal of the city and the environmental stability of the urban landscape.
Common Trees in Boston, Massachusetts
The capital of Massachusetts, Boston, has a population of approximately 650,000 and is renowned for its vibrant cultural scene.
Boston is committed to increasing urban tree canopy coverage from 27% to 35% by 2030 and has regular tree giveaway events to achieve this goal . You can also apply to have a tree planted on the sidewalk in front of your home or business.
An initiative to combat the Emerald Ash Borer which is a threat to the ash trees in the area is also underway.
We analyzed the data on 1,333 trees currently growing in Boston, MA to see which are the most common species found in the city and how diverse the urban forest in Boston is.
Here are the results!
Top 10 Most Common Trees Observed in Boston, MA
- Eastern white pine (Pinus strobus): 20.03%
- Red maple (Acer rubrum): 11.25%
- Northern red oak (Quercus rubra): 8.63%
- Black cherry (Prunus serotina): 6.53%
- Sugar maple (Acer saccharum): 4.43%
- Eastern hemlock (Tsuga canadensis): 3.30%
- Pitch pine (Pinus rigida): 3.15%
- Eastern red cedar (Juniperus virginiana): 2.93%
- White oak (Quercus alba): 2.25%
- Sycamore maple (Acer pseudoplatanus): 2.18%
* All other species combined comprise 35.33% of the total tree population analyzed.
Tree Diversity in Boston, MA
Of the 1,333 tree observed in Boston, at least 78% were categorized as native and 77 unique tree species were observed.
The overwhelmingly dominant species observed was the Eastern white pine (Pinus strobus), accounting for 20% of the total tree population observed in Boston. Other dominant species observed included the Red maple (Acer rubrum), Northern red oak (Quercus rubra), and Black cherry (Prunus serotina).
The effective species number for Boston was calculated to be 24.36. This means that tree diversity in Boston is equivalent to having just 24 species of trees in equal numbers.
The strong presence of native trees in the Boston dataset suggests that the city has a strong connection to the local ecosystem, however, the dominance of a few species and uneven distribution among species indicates a potential for improving the overall species diversity of Boston’s urban canopy.
Common Trees in Buffalo, New York
Buffalo, New York has a population of approximately 280,000 and this is made up of many different ethnic groups.
It has been reported that Buffalo is cutting down up to 4 times the number of trees it is planting, which is a concern for the long-term health of the tree canopy.
Initiatives such as Re Tree New York have surpassed their goal of planting 30,000 trees and advise they are looking to continue planting.
We analyzed the data on 74,815 trees currently growing in Buffalo, NY to see which are the most common species found in the city and how diverse Buffalo’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Buffalo, NY
- Norway maple (Acer platanoides): 13.20%
- Littleleaf linden (Tilia cordata): 12.11%
- Silver maple (Acer saccharinum): 6.32%
- Red maple (Acer rubrum): 3.34%
- Hedge maple (Acer campestre): 3.17%
- Ivory silk lilac (Syringa reticulata): 2.57%
- Crimson king maple (Acer platanoides): 2.51%
- Crabapple (Malus): 2.15%
- Honeylocust (Gleditsia triacanthos): 2.10%
- Elm ‘Christine Buisman’ (Ulmus carpinifolia): 2.06%
* All other species combined comprise 50.49% of the total tree population analyzed.
Tree Diversity in Buffalo, NY
The urban canopy in Buffalo demonstrates considerable diversity of tree species, with a few dominant species. Of the 74,815 trees observed, at least 60% were categorized as non-native, and 218 unique species were observed.
The effective species number was calculated to be 38.03 which means that tree diversity in Buffalo is equivalent to that of a community of 38 species of trees present in equal numbers.
The dominant species observed was the Norway Maple (Acer platanoides) which accounted for 13.2% of the total tree population. Littleleaf Linden (Tilia cordata) made up 12.11% and Silver Maple (Acer saccharinum) was 6.32% of the total population. All other species accounted for less than 4% each of the total 74,815 trees observed.
Common Trees in Cape Coral, Florida
Cape Coral, Florida, has a population of approximately 220,000 and is known for its commitment to urban forestry and tree cover.
Projects like Future Forestry have organized the planting of many trees over a number of years and The Arbor Day Foundation organized the planting of 60 trees after many were lost to Hurricane Ian.
We analyzed the data on 34,021 trees currently growing in Cape Coral, FL to see which are the most common species found in the city and how diverse Cape Coral’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Cape Coral, FL
- Cabbage palm (Sabal palmetto): 19.49%
- Live oak (Quercus virginiana): 16.83%
- Slash pine (Pinus elliottii): 9.69%
- Mahogany (Swietenia macrophylla): 6.67%
- Bald cypress (Taxodium distichum): 5.07%
- Laurel oak (Quercus laurifolia): 2.65%
- Queen palm (Syagrus romanzoffianum): 2.40%
- Florida royal palm (Roystonea regia): 2.18%
- Dahoon holly (Ilex cassine): 1.83%
- Foxtail palm (Wodyetia bifurcata): 1.57%
* All other species combined comprise 31.61% of the total tree population analyzed.
Tree Diversity in Cape Coral, FL
The urban canopy in Cape Coral demonstrates a strong presence of native species, with at least 65% of the 34,021 trees observed categorized as ‘naturally occurring’. The dominance of native trees reflects a healthy connection to the local ecosystem, with introduced species adding to the overall diversity of Cape Coral’s urban forest.
There were 109 unique species of trees in the Cape Coral dataset and the effective species number was calculated to be 15.5. This means that species diversity in Cape Coral is equivalent to having just 16 species of trees in equal numbers.
The most prevalent species observed in Cape Coral were the Cabbage Palm (Sabal palmetto) and the Live Oak (Quercus virginiana), comprising 19.49% and 16.83% of the total tree population, respectively. The top 5 most commonly observed trees account for 58% of the total tree population.
The dominance of a few species, combined with the uneven distribution among species indicate a potential for improved tree species diversity in Cape Coral.
Common Trees in Colorado Springs, Colorado
Colorado Springs is a vibrant city nestled at the foot of the Rocky Mountains and is the 2nd most populated city in Colorado, with a population of approximately 490,000 residents.
Urban development is creating some challenges for the urban tree cover; however, the city is working on maintaining and even increasing the number of trees in the urban landscape.
Initiatives like the Colorado Tree Coalition, which helps local communities plant trees after natural disasters, help maintain tree coverage after disasters strike. They also have various programs such as Trees Across Colorado which provides low-cost deciduous trees to community groups, nonprofits, HOAs and municipalities.
We analyzed the data on 16,051 trees currently growing in Colorado Springs, CO to see which are the most common species found in the city and how diverse the urban forest is.
Here are the results!
Top 10 Tree Species Observed in Colorado Springs, CO
- Ponderosa pine (Pinus ponderosa): 11.99%
- Green ash (Fraxinus pennsylvanica): 11.46%
- Rocky Mountain juniper (Juniperus scopulorum): 6.99%
- Silver maple (Acer saccharinum): 5.93%
- Blue spruce (Picea pungens): 5.52%
- Siberian elm (Ulmus pumila): 5.22%
- American elm (Ulmus americana): 4.23%
- Honeylocust (Gleditsia triacanthos): 3.45%
- Norway maple (Acer platanoides): 3.04%
- Cottonwood (Populus): 2.69%
* All other species combined comprise 39.48% of the total tree population analyzed.
Tree Diversity in Colorado Springs, CO
Colorado Springs demonstrates a mix of both native and non-native tree species, with introduced species dominating the overall tree population. Out of 16,051 trees observed, there were 139 unique species and an effective species number of 26.24. This means that tree diversity in Colorado Springs is equivalent to having 26 species all present in equal numbers.
The most prevalent species observed in Colorado Springs was the Ponderosa Pine (Pinus ponderosa), comprising 11.99% of the total tree population and closely followed by the Green ash (Fraxinus pennsylvanica) comprising 11.46%.
The top 10 most common trees observed in Colorado Springs comprise almost 60% of the total tree population. The dominance of a few species, combined with uneven distribution among species indicates a potential to improve species diversity in Colorado Springs.
Common Trees in Columbus, Ohio
Columbus, the capital city of Ohio, has a population of approximately 900,000 and has a varying tree canopy across its different neighborhoods, according to the Columbus Urban Forestry Master Plan.
Green Columbus is a volunteer-driven non-profit that maintains two tree nurseries and distributes trees at no cost to residents and the community. They also host an earth day every year where volunteers pick up rubbish, among other things.
We analyzed the data on 151,350 trees currently growing in Columbus, OH to see which are the most common species found in the city and how diverse the urban forest in Columbus is.
Here are the results!
Top 10 Tree Species Observed in Columbus, OH
- Green ash (Fraxinus pennsylvanica): 4.83%
- Red maple (Acer rubrum): 4.78%
- Callery pear (Pyrus calleryana): 4.43%
- Sugar maple (Acer saccharum): 4.28%
- Honey locust (Gleditsia triacanthos): 4.24%
- Crabapple (Malus): 3.96%
- White ash (Fraxinus americana): 3.89%
- Freeman maple (Acer freemanii): 3.17%
- Norway maple (Acer platanoides): 2.54%
- Littleleaf linden (Tilia cordata): 2.39%
* All other species combined comprise 61.49% of the total tree population analyzed.
Tree Diversity in Columbus, Ohio
Urban tree cover in Columbus is made of a rich combination of both native and introduced species. Of the 151,350 trees observed, approximately 48% of the trees were categorized as native, 30% as introduced and the remaining 22% were uncategorized.
The number of unique tree species observed was an impressive 245 and the effective species number was calculated to be 38.06. This means that tree diversity in Columbus is akin to having 38 species of trees in equal numbers.
The top 10 most commonly observed trees in Columbus comprise less than 39% of the total tree population, with the dominant species being Green Ash (Fraxinus pennsylvanica), accounting for 4.83% of the total population.
The presence of both native and non-native species, along with the large variety of unique species, contributes to the overall diversity, aesthetic appeal and sustainability of Columbus’s urban forest.
Common Trees in Dallas, Texas
Dallas, Texas, is the third largest city in the state and currently has a population of approximately 1.3 million people.
According to Texas Trees, there are estimated to be nearly 15 million trees growing around Dallas, with nearly 50% of these growing in the Great Trinity Forest.
The Urban Forest Master Plan aims to go from 32% urban tree canopy coverage to 37% by 2040. The Branching Out program is helping to plant trees in parks and also offers residents the opportunity to get a free tree for their yard every November.
We analyzed the data on 6,218 trees currently growing in Dallas, TX to see which are the most common species found in the city and how diverse the urban forest in Dallas is.
Here are the results!
Top 10 Tree Species Observed in Dallas, TX
- Live oak (Quercus virginiana): 19.91%
- Cedar elm (Ulmus crassifolia): 13.57%
- Shumard oak (Quercus shumardii): 12.24%
- Baldcypress (Taxodium distichum): 11.11%
- Common crapemyrtle (Lagerstroemia indica): 7.99%
- Chinese pistache (Pistacia chinensis): 6.87%
- Chinese elm (Ulmus parvifolia): 4.66%
- Sweetgum (Liquidambar styraciflua): 4.62%
- Southern magnolia (Magnolia grandiflora): 2.56%
- Callery pear (Pyrus calleryana): 2.44%
* All other species combined comprise 14.02% of the total tree population analyzed.
Tree Diversity in Dallas, TX
The urban forest in Dallas has a strong emphasis on native trees, with 73% of the 6,218 observed trees categorized as naturally occurring. Prominent native species include the Live Oak (Quercus virginiana) and Cedar Elm (Ulmus crassifolia) which account for 19.91% and 13.57% of the total tree population, respectively.
The ten most commonly observed trees make up nearly 86% of the total tree population with the top five accounting for almost 65%. This demonstrates a potentially overwhelming dominance of just a handful of tree species in Dallas.
Only 50 unique species were observed in the dataset and the effective species number is 14.39. This means that tree diversity in Dallas is akin to having just 14 species of trees in equal numbers.
Common Trees in Denver, Colorado
Denver, the capital of Colorado, has a population of over 700,000 and is known for its outdoor recreational opportunities.
The city has a diverse range of tree species and is committed to ensuring its urban forest continues to grow. Initiatives like Denver Digs Trees help residents, businesses, and schools get access to subsidized tree costs and in some cases free trees if you are facing financial hardship.
Denver Parks also launched the “Be a Smart Ash” campaign to try and combat the Emerald Ash Borer which they claim could kill up to 15% of Denver trees, equating to around 330,000 ash trees. Through education and even offering free trees to plant, the city is doing its best to combat this issue.
We analyzed the data on 283,284 trees currently growing in Denver, CO to see which are the most common species found in the city and how diverse Denver’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Denver, CO
- Green ash (Fraxinus pennsylvanica): 9.08%
- Honey locust (Gleditsia triacanthos): 8.32%
- Littleleaf linden (Tilia cordata): 4.58%
- Silver maple (Acer saccharinum): 4.50%
- White ash (Fraxinus americana): 4.21%
- Siberian elm (Ulmus pumila): 3.77%
- Freeman maple (Acer freemanii): 3.45%
- Flowering crabapple (Malus sylvestris): 3.26%
- Northern hackberry (Celtis occidentalis): 3.20%
- Norway maple (Acer platanoides): 2.80%
* All other species combined comprise 52.83% of the total tree population analyzed.
Tree Diversity in Denver, CO
The urban forest in Denver is made up of a rich blend of tree species, both introduced and native. Out of the 283,284 trees observed, at least 80% were categorized as introduced (non-native) and 317 unique tree species were identified. This demonstrates a rich diversity of trees contributing to urban tree cover in Denver.
The effective species number was an impressive 55.7, which means species diversity in Denver is equivalent to having 56 species of trees in equal numbers.
The most prevalent species observed were the Green Ash (Fraxinus pennsylvanica) and Honey Locust (Gleditsia triacanthos), which accounted for 9.08% and 8.32% of the total tree population, respectively, significantly outnumbering other species.
Other dominant species observed include Littleleaf Linden (Tilia cordata), Silver Maple (Acer saccharinum), and White Ash (Fraxinus americana), with each species contributing between 4-5% to the total tree population.
With a high number of unique species and less than 50% of the tree population comprising the top 10 trees, the data suggests that Denver has a complex and impressive urban forest. The dominance of introduced species may indicate the need to focus on native species in future plantings.
Common Trees in Des Moines, Iowa
Des Moines, Iowa has a population of over 210,000 people making it the most populated city in Iowa.
This great city is recognized for its commitment to ensuring its urban tree cover increases over the coming years. One such way is by offering residents free trees.
The Tiny Trees program has provided tens of thousands of free trees to residents of Des Moines since 2017. Residents are able to request up to 5 free trees from the Forestry Division which is a great way to increase the urban tree canopy in the city. Tree Des Moines is another great initiative that is helping to restore and protect the urban tree canopy.
We analyzed the data on 15,805 trees currently growing in Des Moines, IA, to see which are the most common species found in the city and how diverse the urban forest is.
Here are the results!
Top 10 Tree Species Observed in Des Moines, IA
- Green ash (Fraxinus pennsylvanica): 9.86%
- Apple (Malus): 7.99%
- Silver maple (Acer saccharinum): 7.61%
- Sugar maple (Acer saccharum): 6.88%
- Norway maple (Acer platanoides): 4.50%
- Northern hackberry (Celtis occidentalis): 4.45%
- Bur oak (Quercus macrocarpa): 4.16%
- Eastern white pine (Pinus strobus): 3.50%
- Northern red oak (Quercus rubra): 3.41%
- Spruce (Picea): 3.14%
* All other species combined comprise 44.50% of the total tree population analyzed.
Tree Diversity in Des Moines, IA
The urban canopy in Des Moines has a significant number of native trees, including prominent species such as Green Ash (Fraxinus pennsylvanica) and Silver Maple (Acer saccharinum).
Of the 15,805 trees observed in the dataset, 9,866 were categorized as native and 85 unique tree species were identified. The effective species number was calculated to be 35.53, meaning species diversity in Des Moines is equivalent to having 36 species of trees in equal numbers.
Other notable tree species contributing to the urban forest in Des Moines include Apple trees (Malus spp.), Sugar Maple (Acer saccharum), and Norway Maple (Acer platanoides). This means that three of the five most commonly observed trees in Des Moines are a species of maple.
Common Trees in Detroit, Michigan
Detroit, Michigan, has a population of approximately 620,000 people and is known for its contribution to the automotive industry.
In recent years Detroit has been working on improving its urban tree cover by launching the “10,000 Up” initiative. With a goal of planting 10,000 trees to replace trees lost to age and disease, they are halfway there. Several thousand trees are still up for grabs and residents can request a free tree be planted at their home near the pavement.
Another great program that has planted over 135,000 trees is Greening of Detroit, which helps educate and train volunteers on the importance of trees and their care.
We analyzed the data on 20,375 trees currently growing in Detroit, MI to see which are the most common species found in the city and how diverse Detroit’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Detroit, MI
- Willow (Salix): 8.52%
- Cottonwood (Populus): 6.26%
- Red maple (Acer rubrum): 4.89%
- Elm (Ulmus): 4.22%
- Common hackberry (Celtis occidentalis): 4.18%
- Swamp white oak (Quercus bicolor): 3.45%
- London planetree (Platanus acerifolia): 2.94%
- Tulip tree (Liriodendron tulipifera): 2.94%
- Kentucky coffeetree (Gymnocladus dioicus): 2.65%
- Northern red oak (Quercus rubra): 2.63%
* All other species combined comprise 57.32% of the total tree population analyzed.
Tree Diversity in Detroit, MI
In Detroit, 20,375 trees were observed and 97 unique species were identified. The effective species number was calculated to be 39.5, which means tree diversity in Detroit is akin to having 40 different species of trees in equal numbers.
The ten most commonly observed trees only accounted for 42.68% of the population, a good indication of diversity among the species contributing to Detroit’s urban forest.
The most dominant species observed were Willow trees from the Salix genus which comprise 8.52% of the total population of trees. Other prevalent species include Cottonwood (Populus spp.), Red Maple (Acer rubrum), and Elm (Ulmus spp.).
The presence of the Tulip tree (Liriodendron tulipifera) and Northern red oak (Quercus rubra) in the ten most commonly observed trees paints a picture of a visually diverse and interesting urban forest in Detroit.
Common Trees in Durham, North Carolina
Durham, North Carolina, has a population of over 330,000 and is very proactive when it comes to ensuring its urban tree canopy is healthy.
Initiatives by the city of Durham include the goal of planting 1,500 new street trees every year throughout 2025. Trees Durham is dedicated to not only planting trees via their tree planting events but also educating others on the importance of trees and all their benefits.
Another initiative, Keep Durham Beautiful, offers multiple tree-planting opportunities throughout the year. They also provide volunteers with the tools and skills to plant and take care of trees.
We analyzed the data on 16,014 trees currently growing in Durham, NC to see which are the most common species found in the city and how diverse Durham’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Durham, NC
- Common crapemyrtle (Lagerstroemia) – 19.38%
- Willow oak (Quercus phellos) – 17.34%
- Trident maple (Acer buergerianum) – 6.41%
- Red maple (Acer rubrum) – 4.48%
- Chinese elm (Ulmus parvifolia) – 3.58%
- Eastern redbud (Cercis canadensis) – 3.35%
- American elm (Ulmus americana) – 2.34%
- Chinese pistache (Pistacia chinensis) – 2.27%
- Overcup oak (Quercus lyrata) – 2.04%
- Ginkgo (Ginkgo biloba) – 1.63%
* All other species combined comprise 37.18% of the total tree population analyzed.
Tree Diversity in Durham, NC
Out of 16,014 trees observed, there was an overwhelming dominance of two tree species in Durham. Common Crapemyrtle (Lagerstroemia) and Willow Oak (Quercus phellos) together account for nearly 37% of the total tree population (5,880 out of 16,014 trees).
Despite the dominance of these two species, Durham has a reasonably diverse urban forest with 141 unique tree species identified and a unique species number of 29.69. This means tree diversity in Durham is akin to having 30 species of trees in even numbers.
Of the trees observed, just over half (51.01%) were categorized as naturally occurring (native) and 25.18% were categorized as introduced (non-native) with the remaining trees remaining uncategorized.
The considerable number of unique species and blend of both native and non-native trees contribute to the overall diversity, sustainability and aesthetic appeal of the city’s urban tree cover. However, the significant dominance of Crapemyrtle and Willow Oak indicates a need for further species diversification in Durham.
Common Trees in Fresno, California
Fresno is located near the Yosemite National Park and Sierra Nevada mountains and is the 5th most populated city in California with approximately 545,000 residents.
Like many urban areas, Fresno faces challenges in maintaining and increasing its tree cover, so initiatives like Tree Fresno, aiming to plant 20,000 trees by 2030, will certainly help the cause.
Another great initiative, “City of Fresno Tree Policy,” introduced by Fresno City Council and in partnership with CalFire’s Urban Forestry division, proposes to plant a minimum of 1,000 drought-tolerant trees on public property each year until 2035.
We analyzed the data on 6,572 trees currently growing in Fresno, CA, to see which are the most common species found in the city and how diverse Fresno’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Fresno, CA
- Deodar cedar (Cedrus deodara): 11.40%
- Chinese pistache (Pistacia chinensis): 10.85%
- Valley oak (Quercus lobata): 8.95%
- Chinese elm (Ulmus parvifolia): 6.76%
- Scarlet oak (Quercus coccinea): 6.04%
- Ginkgo (Ginkgo biloba): 5.04%
- London planetree (Platanus acerifolia): 4.47%
- Italian stone pine (Pinus pinea): 3.62%
- Southern live oak (Quercus virginiana): 3.53%
- Aleppo pine (Pinus halepensis): 3.18%
* All other species combined comprise 36.17% of the total tree population analyzed.
Tree Diversity in Fresno, CA
A substantial number of the 6,572 trees observed in Fresno were categorized as introduced (non-native) with only one tree (the Valley Oak) in the five most commonly observed trees categorized as native.
The dominant tree species observed in Fresno is the Deodar cedar (Cedrus deodara), comprising 11.4% of the total tree population, closely followed by the Chinese pistache (Pistacia chinensis) at 10.85%.
A total of 60 unique tree species were observed and the effective species number was calculated to be 19.88, meaning that tree diversity in Fresno is tantamount to having just 20 species in equal numbers.
Among the top 10 most commonly observed tree species in Fresno, there were three species of oak (Valley Oak, Scarlet Oak and Southern Live Oak) and two species of pine (Aleppo Pine and Stone Pine). This data suggests a potential for improvement in overall tree diversity in Fresno with an emphasis on increasing native tree species numbers.
Common Trees in Garden Grove, California
Garden Grove, California, once known for its crops of oranges, has a population of approximately 170,000.
Garden Groves Urban Forest Management Plan states they currently have 7.9% canopy cover (2019) and aim to increase it to 15%. The city of Garden Grove also promotes its “adopt a tree” program, where, for $75, you can request for a tree to be planted. You are responsible for watering and they will handle the trimming and care.
We analyzed the data on 17,399 trees currently growing in Garden Grove, CA to see which are the most common species found in the city and how diverse the urban forest is.
Here are the results!
Top 10 Tree Species Observed in Garden Grove, CA
- Crape myrtle (Lagerstroemia indica): 13.54%
- Brisbane box (Lophostemon confertus): 9.44%
- Carrotwood (Cupaniopsis anacardioides): 8.26%
- Canary Island pine (Pinus canariensis): 6.03%
- Queen palm (Syagrus romanzoffianum): 5.16%
- Evergreen pear (Pyrus kawakamii): 4.08%
- Southern magnolia (Magnolia grandiflora): 3.99%
- Jacaranda (Jacaranda acutifolia): 3.84%
- Mexican fan palm (Washingtonia robusta): 3.42%
- London plane (Platanus acerifolia): 3.41%
* All other species combined comprise 38.83% of the total tree population analyzed.
Tree Diversity in Garden Grove, CA
The dataset for Garden Grove included observations on 17,399 individual trees, and out of those, 223 unique species were identified. The effective species number is 35.52, which means that tree diversity in Garden Grove is akin to having 36 different tree species in equal numbers.
The urban forest in Garden Grove is dominated by Crape myrtle (Lagerstroemia indica), the most prevalent species observed, accounting for 13.54% of the total tree population.
Other dominant species in Garden Grove include Brisbane box (Lophostemon confertus), Carrotwood (Cupaniopsis anacardioides), Canary island pine (Pinus canariensis) and Queen palm (Syagrus romanzoffianum).
While there does appear to be a reasonable diversity of species in the Garden Grove dataset, the overwhelming majority of trees are categorized as introduced (over 83%), with only 2.29% classified as native. The remaining trees (14.52%) were not categorized in either category.
This data indicates that while the urban forest in Garden Grove is richly diverse, there is potential for improvement by increasing the population of native tree species.
Common Trees in Grand Rapids, Michigan
Grand Rapids, Michigan, or “River City,” has a population of approximately 200,000 people.
In 2016 the mayor launched the “Mayors Greening Initiative” with the goal of planting trees in an area of the city that has low tree canopy cover. They aim to plant 300+ trees in different neighborhoods each year.
Friends of GR Parks has a free tree program where they award funding to interested groups that want to do a planting, and they offer 10-30 trees to successful applicants.
We analyzed the data on 72,077 trees growing in Grand Rapids, MI to see which are the most common species in the city and how diverse the urban forest is in Grand Rapids.
Here are the results!
Top 10 Tree Species Observed in Grand Rapids, MI
- Norway maple (Acer platanoides) – 28.34%
- Thornless honeylocust (Gleditsia triacanthos) – 7.99%
- Red maple (Acer rubrum) – 6.28%
- Sugar maple (Acer saccharum) – 5.49%
- Littleleaf linden (Tilia cordata) – 4.21%
- American sycamore (Platanus occidentalis) – 4.13%
- Silver maple (Acer saccharinum) – 3.54%
- Green ash (Fraxinus pennsylvanica) – 2.85%
- London planetree hybrid (Scientific name not available) – 2.68%
- Callery pear (Pyrus calleryana) – 2.31%
* All other species combined comprise 32.19% of the total tree population analyzed.
Tree Diversity in Grand Rapids, MI
The urban canopy in Grand Rapids is comprised of a balanced mix of both native and introduced (non-native) tree species. Out of the 72,077 trees observed, 165 unique species were identified and an effective species number of 22.36 was calculated. This means that tree diversity in Grand Rapids is akin to having 22 different tree species in equal numbers.
Among the most prevalent species observed were the native Thornless honeylocust (Gleditsia triacanthos), Red maple (Acer rubrum) and Sugar maple (Acer saccharum). However, the introduced Norway maple (Acer platanoides) is the overwhelmingly dominant species, accounting for a huge 28.34% of the total population of trees observed.
The dominance of a single species combined with the uneven distribution among species indicates the potential for improvement in overall species diversity in Grand Rapids. The presence of four maple species in the top ten most commonly observed trees also indicates a need for further diversification at a Genus level.
Common Trees in Greensboro, North Carolina
Greensboro is the 3rd most populated city in North Carolina, with a population of over 300,000.
The City of Greensboro, the NC Cooperative Extension Service, and Greensboro Beautiful have partnered to create the Neighborwoods community tree planting program.
This program is funded by tax-deductible donations and allows residents to request up to two native trees to be planted as street trees around their property. Residents can also volunteer to help plant trees.
We analyzed the data on 6,581 trees growing in Greensboro, NC, to see which are the most common species in the city and how diverse Greensboro’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Greensboro, NC
- Crape myrtle (Lagerstroemia indica) – 11.29%
- Willow oak (Quercus phellos) – 7.95%
- Pecan (Carya illinoinensis) – 6.64%
- Elm (Ulmus) – 5.97%
- Hackberry (Celtis occidentalis) – 4.48%
- Sugar maple (Acer saccharum) – 3.62%
- Dogwood (Cornus florida) – 3.46%
- Mulberry (Morus) – 3.36%
- Black walnut (Juglans nigra) – 3.34%
- Red maple (Acer rubrum) – 3.13%
* All other species combined comprise 46.76% of the total tree population analyzed.
Tree Diversity in Greensboro, NC
Out of 6,581 trees observed in the Greensboro dataset, an impressive 351 unique species were identified. Additionally, the unique species number was calculated to be 52.81, meaning that tree diversity in Greensboro is equivalent to having 53 species in equal numbers, indicating a richly diverse urban forest.
The dominant species observed in Greensboro was the non-native Crape myrtle (Lagerstroemia indica), comprising 11.29% of the total tree population. Other prevalent species include the native Willow oak (Quercus phellos) and Pecan (Carya illinoinensis), contributing 7.95% and 6.64% to the total tree population, respectively.
Among the ten most common tree species observed in Greensboro, nine out of ten were categorized as naturally occurring (native). The strong presence of native species highlights Greensboro’s commitment to maintaining and enhancing native biodiversity within the city’s urban forest.
Common Trees in Honolulu, Hawaii
Honolulu has stunning natural beauty and is the capital city of Hawaii, with a population of approximately 340,000.
The U.S. Forest Service has indicated that Honolulu lost more than 76,000 trees during a four-year period. However, the city plans to plant 100,000 trees by 2025 to increase urban canopy coverage from 25% to 35%. According to Resilient Oahu, they are just over halfway there, with 53,000 + trees planted so far.
Groups like Trees for Honolulu are mapping trees for planting locations, helping drought-stressed trees, and educating people about the importance of keeping trees alive and healthy.
We analyzed the data on 7,151 trees currently growing in Honolulu, HI, to see which are the most common species found in the city and how diverse Honolulu’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Honolulu, HI
- Monkeypod (Albizia saman) – 10.04%
- Coconut palm (Cocos nucifera) – 8.88%
- Rainbow shower (Cassia nealiae) – 8.05%
- Pink tecoma (Tabebuia heterophylla) – 5.89%
- Formosan koa (Acacia confusa) – 4.64%
- Manila palm (Adonidia merrillii) – 3.40%
- Fiji fan palm (Pritchardia pacifica) – 2.60%
- Chinese banyan (Ficus microcarpa) – 2.50%
- False olive (Cassine orientalis) – 2.28%
- White tecoma (Tabebuia berteroi) – 2.25%
* All other species combined comprise 49.46% of the total tree population analyzed.
Tree Diversity in Honolulu, HI
The ecologically diverse Honolulu has an urban canopy that is made up of a mixture of native and introduced tropical and subtropical tree species.
Among the 7,151 trees observed, 175 unique species were identified, with an effective species number of 48.14. This demonstrates the rich diversity of the urban canopy in Honolulu, as this is tantamount to having 48 species of trees in equal numbers.
The top ten most commonly observed trees account for roughly 50% of Honolulu’s total tree population; the dominant species accounting for 10.04% of the population is the Monkeypod (Albizia saman).
Other prevalent species include the Coconut Palm (Cocos nucifera), Rainbow Shower (Cassia nealiae), and Pink Tecoma (Tabebuia heterophylla), the presence of which paints a picture of a colorful, tropical paradise.
Common Trees in Houston, Texas
Houston, Texas, is the fourth most populated city in the United States, with a population of approximately 2.3 million.
Trees for Houston is dedicated to planting, protecting, and promoting trees in the city and encourages residents to volunteer and donate to their great cause.
The city aims to plant 4.6 million new trees by 2030, with the ambitious goal currently underway.
We analyzed the data on 213,388 trees growing in Houston, TX, to see which are the most common species found in the city and how diverse Houston’s urban forest is.
Here are the results!
Top 10 Tree Species Observed in Houston, TX
- Crape myrtle (Lagerstroemia indica) – 20.77%
- Live oak (Quercus virginiana) – 20.65%
- Common hackberry (Celtis occidentalis) – 6.10%
- Water oak (Quercus nigra) – 5.05%
- Chinese tallow (Triadica sebifera) – 4.48%
- Loblolly pine (Pinus taeda) – 4.17%
- Pecan (Carya illinoinensis) – 2.87%
- Palm (Washingtonia robusta) – 2.56%
- Southern magnolia (Magnolia grandiflora) – 2.01%
- Arizona ash (Fraxinus velutina) – 1.77%
* All other species combined comprise 29.57% of the total tree population analyzed.
Tree Diversity in Houston, TX
The Houston dataset included observations on 213,388 trees, and among these, 220 unique species were identified. The effective species number for Houston was calculated to be 22.53, meaning that tree diversity in Houston is equivalent to having just 23 species of trees in even numbers.
The urban canopy in Houston is made up of a good blend of both native (58.6%) and non-native (36%) trees (with 5.4% uncategorized).
Among the observed trees, two species were overwhelmingly dominant, the Crape Myrtle (Lagerstroemia indica) and Live Oak (Quercus virginiana), with both accounting for just over 20% of the total tree population. This means over 40% of all trees observed comprised just two species.
The top ten most commonly observed trees in Houston accounted for over 70% of the total tree population, further highlighting the potential need for improved diversification among tree species in Houston.
Common Trees in Huntington Beach, California
Huntington Beach, California, has a population of approximately 195,000 and is known for its surfing and sandy beaches.
The city is also home to a stunning urban forest that is located in Central Park. The forest is kept in excellent condition by weekly volunteers from the Huntington Beach Tree Society who weed, plant and perform tree care.
Shadetree Partnership operates a 5 ½ acre nursery on the campus of the University of California. There are currently 4,000 trees and shrubs growing there that are nurtured by volunteers. They have planted more than 36,500 trees since inception in 1990.
We analyzed the data on 45,219 trees already growing in Huntington Beach, CA, to see which are the most common species in the city and how diverse the urban forest is.
Here are the results!
Top 10 Tree Species Observed in Huntington Beach, CA
- Queen palm (Syagrus romanzoffianum) – 10.35%
- Mexican fan palm (Washingtonia robusta) – 8.93%
- Crape myrtle (Lagerstroemia indica) – 8.43%
- Red gum (Eucalyptus camaldulensis) – 5.69%
- King palm (Archontophoenix cunninghamiana) – 3.68%
- Eastern redbud (Cercis canadensis) – 3.24%
- Brisbane box (Lophostemon confertus) – 3.21%
- Carrotwood (Cupaniopsis anacardioides) – 3.16%
- Canary Island pine (Pinus canariensis) – 2.99%
- Lemon bottlebrush (Melaleuca citrina) – 2.57%
* All other species combined comprise 47.74% of the total tree population analyzed.
Tree Diversity in Huntington Beach, CA
Huntington Beach has a richly diverse urban forest with 294 unique tree species observed in this analysis. We calculated the effective species number to be 49.44 which means tree diversity in Huntington Beach is equivalent to having 49 tree species in equal numbers.
Of the 45,219 trees observed, 34,467 (76%) were categorized as introduced (non-native). The Queen palm (Syagrus romanzoffianum) and Mexican fan palm (Washingtonia robusta) are the most dominant among the introduced tree species.
Other prevalent species include the Crape myrtle (Lagerstroemia indica), Red gum (Eucalyptus camaldulensis), and King palm (Archontophoenix cunninghamiana).
Overall, the urban forest in Huntington Beach showcases a wide variety of different tree species and an emphasis on non-native species. The presence of several palms in the top 5 most commonly observed trees reflects the city’s coastal environment. The dominance of certain species combined with the uneven distribution among species does suggest some further diversification would be beneficial, particularly of native species, to support the local ecosystems.
Common Trees in Indianapolis, Indiana
Indianapolis, the capital city of Indiana, has a population of approximately 880,000 and is working on improving its urban tree cover.
Urban development is increasing, causing many acres of trees to be cut down. Many of the city’s large urban forests are privately owned, putting them in the hands of the city’s development commission.
There are some great initiatives doing good things, and one of them – Keep Indianapolis Beautiful, has a goal of planting 100,000 large trees in strategic locations. They have also partnered with Citizens Energy Group and the City of Indianapolis to plant 10,000 trees across the city.
In 2019, the “Thrive Indianapolis” plan was released, which aimed to plant 30,000 additional native trees by 2025. This goal has been achieved two years early.
We analyzed the data on 97,227 trees currently growing in Indianapolis, IN, to see which are the most common species found in the city, and how diverse the tree population is.
Here are the results!
Top 10 Tree Species Observed in Indianapolis, IN
- Sugar Maple (Acer saccharum) – 7.24%
- Hackberry (Celtis occidentalis) – 6.11%
- Apple (Malus) – 5.97%
- White Ash (Fraxinus americana) – 5.88%
- Siberian Elm (Ulmus pumila) – 4.09%
- Norway Maple (Acer platanoides) – 3.39%
- Eastern White Pine (Pinus strobus) – 3.24%
- Red Maple (Acer rubrum) – 3.22%
- Mulberry (Morus) – 3.20%
- Green Ash (Fraxinus pennsylvanica) – 2.89%
* All other species combined comprise 54.77% of the total tree population analyzed.
Tree Diversity in Indianapolis, IN
Out of 97,227 trees observed in Indianapolis, at least 60% were categorized as native and 171 unique species of both native and non-native trees were observed. The effective species number was calculated to be 48.81 which means that tree diversity in Indianapolis is akin to having 49 different tree species in equal numbers.
The most dominant species observed in Indianapolis was the Sugar Maple (Acer saccharum), comprising 7.24% of the total tree population analyzed. Other commonly observed species include Hackberry (Celtis occidentalis), Apple trees (Malus spp.), and White Ash (Fraxinus americana).
The top 10 most commonly observed trees account for 45.23% of the total tree population, demonstrating that although the urban forest in Indianapolis is reasonably diverse, the uneven distribution among species indicates a potential for further improvements in diversity.
Overall, the urban forest in Indianapolis reflects a rich blend of tree species, which, due to the dominance of native species, resonates with the local ecosystem.
Common Trees in Irvine, California
Irvine, California, has a population of approximately 315,000 and has been a “Tree City USA” for over 30 years.
The University of California, Irvine (UCI) and Irvine Ranch Water District (IRWD) partnered with the non-profit Shadetree Nursery program nearly twenty years ago and have been integral in planting over 30,000 shade trees.
We analyzed the data on 58,364 trees currently growing in Irvine, CA, to see which are the most common species found in the city, and how diverse the tree population is.
Here are the results!
Top 10 Tree Species Observed in Irvine, CA
- Canary Island pine (Pinus canariensis) – 7.84%
- Blue gum eucalyptus (Eucalyptus globulus) – 6.76%
- Spotted gum (Eucalyptus maculata) – 6.56%
- Brisbane box (Tristaniopsis Brongn.) – 6.53%
- Turkish pine (Pinus brutia) – 5.72%
- Aleppo pine (Pinus halepensis) – 5.09%
- California sycamore (Platanus racemosa) – 4.95%
- Gum (Eucalyptus) – 4.29%
- Jacaranda (Jacaranda mimosifolia) – 3.53%
- Sweetgum (Liquidambar styraciflua) – 3.04%
* All other species combined comprise 45.68% of the total tree population analyzed.
Tree Diversity in Irvine, CA
The data analyzed on 58,364 trees in Irvine suggests that its urban forest is dominated by introduced tree species such as the Canary Island Pine (Pinus canariensis), Blue Gum Eucalyptus (Eucalyptus globulus), Spotted Gum (Eucalyptus maculata) and Brisbane Box (Tristaniopsis Brongn.).
The most dominant native species observed in Irvine was the California Sycamore (Platanus racemosa), accounting for 4.95% of the total tree population observed.
One hundred thirty unique species were identified in Irvine, and the effective species number was calculated to be 37.15. This means that tree diversity in the city is equivalent to having 37 species in equal numbers.
The combination of native and introduced trees adds to the visual appeal and functionality of Irvine’s city landscape. However, the dominance of certain species and the uneven distribution among species indicate that further diversification may be beneficial, particularly of native tree species.
Common Trees in Kailua, Hawaii
Kailua is a census-designated place in Hawaii with a population of approximately 40,500 and is committed to maintaining and enhancing its urban tree cover.
In 2016, a group of passionate volunteers formed to become known as the Kailua Citizen Forester Program. With the help of arborists and mapping specialists, they learned how to identify trees and have been plotting trees in the hopes of having every tree in the region included in the database. You can visit the tree plotter database here.
While not specific to Kailua, O’ahu has committed to planting 100,000 trees by 2025.
We analyzed the data on 5,419 trees currently growing in Kailua, HI, to see which are the most common species found in the area and how diverse the tree population is.
Here are the results!
Top 10 Tree Species Observed in Kailua, HI
- Manila palm (Adonidia merrillii) – 18.14%
- Coconut palm (Cocos nucifera) – 18.10%
- Pink tecoma (Tabebuia heterophylla) – 6.88%
- Ironwood (Casuarina equisetifolia) – 5.91%
- Silver buttonwood (Conocarpus erectus) – 4.63%
- Rainbow shower (Cassia nealiae) – 4.04%
- Fern tree (Filicium decipiens) – 3.28%
- Haole kou (Cordia sebestena) – 3.14%
- Kamani (Calophyllum inophyllum) – 2.29%
- Paraguay tea (Ilex paraguariensis) – 2.20%
* All other species combined comprise 31.39% of the total tree population analyzed.
Tree Diversity in Kailua, HI
The unique coastal landscape of Kailua is reflected in the tree species observed in this analysis. Out of 5,419 trees analyzed, 133 unique species were identified, and the effective species number was calculated to be 25.71. This means tree diversity in Kailua is akin to having 26 species in equal numbers.
The dominant species observed were the Manila Palm (Adonidia merrillii) and Coconut Palm (Cocos nucifera), accounting for 18% of the total tree population and significantly outnumbering other species.
The next most prevalent species observed included the Pink Tecoma (Tabebuia heterophylla) and Ironwood (Casuarina equisetifolia). The strong presence of other species, such as the Rainbow Shower (Cassia nealiae) and Fern Tree (Filicium decipiens), showcases Kailua’s colorful and lush tropical landscape.
Despite its visual appeal, the dominance of a few species in this dataset suggests that further diversification of tree species in Kailua may be needed to promote ecological sustainability and ecosystem integrity within the area.
Common Trees in Kaneohe, Hawaii
Kaneohe, a census-designated place in Honolulu County, Hawaii, has a population of approximately 35,000 and is known for its natural beauty and Hoʻomaluhia Botanical Garden. With 400 lush acres of stunning flora and fauna, it is no wonder this garden is named “a peaceful refuge.”
We analyzed the data on 2,058 trees currently growing in Kaneohe, HI, to see which are the most common species found in the region.
Here are the results!
Top 10 Tree Species Observed in Kaneohe, HI
- Manila palm (Adonidia merrillii) – 14.43%
- Rainbow shower (Cassia nealiae) – 7.48%
- Pink tecoma (Tabebuia heterophylla) – 7.05%
- Myrtle crape (Lagerstroemia indica) – 6.27%
- Coconut palm (Cocos nucifera) – 5.05%
- Fern tree (Filicium decipiens) – 3.74%
- Palm (Arecaceae) – 3.69%
- Satinleaf (Chrysophyllum oliviforme) – 3.45%
- Silver buttonwood (Conocarpus erectus) – 3.11%
- Paperbark (Melaleuca quinquenervia) – 2.92%
* All other species combined comprise 42.81% of the total tree population analyzed.
Tree Diversity in Kaneohe, HI
With 109 unique tree species observed in this analysis, the data indicates that Kaneohe has a reasonably diverse urban forest. The dominant species observed was the Manila Palm (Adonidia merrillii), which accounts for 14.43% of the total tree population, significantly outnumbering other species.
The effective species number for Kaneohe was calculated to be 38.97, which means tree diversity in the region is akin to having 39 species in equal numbers.
Other dominant species present in the analysis included the Rainbow Shower (Cassia nealiae), Pink Tecoma (Tabebuia heterophylla), and Crape Myrtle (Lagerstroemia indica). The presence of these colorful tropical trees emphasizes the visual appeal and ecological richness of Kaneohe’s urban forest.
Common Trees in Knoxville, Tennessee
Knoxville, Tennessee, has a population of approximately 195,000, and every year, the city plants between 400 and 500 trees along the city streets and throughout parks.
You can request trees to be planted in your neighborhood, and a PDF showing the most suitable options can be found here.
Trees Knoxville, a volunteer training program, plants, on average, 144 trees a year and offers a certificate program where they train and educate on tree selection and planting.
We analyzed the data on 8,382 trees currently growing in Knoxville, TN to see which are the most common species found in the city.
Here are the results!
Top 10 Most Common Trees Observed in Knoxville, TN
- Red maple (Acer rubrum) – 8.15%
- Flowering dogwood (Cornus florida) – 7.18%
- Sugar maple (Acer saccharum) – 7.09%
- Common crapemyrtle (Lagerstroemia indica) – 6.17%
- Eastern redbud (Cercis canadensis) – 3.85%
- Willow oak (Quercus phellos) – 3.83%
- Common hackberry (Celtis occidentalis) – 3.36%
- Eastern white pine (Pinus strobus) – 2.37%
- Pin oak (Quercus palustris) – 2.20%
- Silver maple (Acer saccharinum) – 2.05%
* All other species combined comprise 53.75% of the total tree population analyzed.
Tree Diversity in Knoxville, TN
Out of 8,382 trees observed, over 66% were categorized as native and 153 unique species were identified. The effective species number was calculated to be 56.2, which means tree diversity in Knoxville is akin to having 56 species in equal numbers.
The data reflects a diverse array of deciduous and evergreen trees contributing to the city’s urban forest, with a dominance of native species such as Red Maple (Acer rubrum), Flowering Dogwood (Cornus florida), and Sugar Maple (Acer saccharum). These, combined with introduced (non-native) species such as the Common Crapemyrtle (Lagerstroemia indica) and Southern Magnolia (Magnolia grandiflora), paint a colorful and attractive picture of the Knoxville landscape.
Overall, the data on Knoxville’s urban forest showcases a wide variety of species with a significant emphasis on native trees.
Common Trees in Las Vegas, Nevada
Las Vegas, Nevada, has a population of over 650,000 and is known for its vibrant nightlife. Not only is Las Vegas part of Tree City USA, but the Mayor’s Fund for Las Vegas LIFE is aiming to raise funding to plant 60,000 trees by 2050.
The city also has set the goal of increasing urban tree canopy by 20% by 2035.
We analyzed the data on 31,864 trees currently growing in Las Vegas, NV, to see which are the most common species found in the city and how diverse they are.
Top 10 Most Common Trees Observed in Las Vegas, NV
- Afghan pine (Pinus brutia) – 18.48%
- Velvet ash (Fraxinus velutina) – 14.06%
- Mexican fan palm (Washingtonia robusta) – 5.79%
- Shoestring acacia (Acacia stenophylla) – 4.65%
- Chaste tree (Vitex agnus-castus) – 4.64%
- Chilean mesquite (Prosopis chilensis) – 4.02%
- Narrow leaf ash (Fraxinus angustifolia) – 3.56%
- Chitalpa (Chitalpa tashkentensis) – 3.30%
- Desert willow (Chilopsis linearis) – 3.20%
- Date palm (Phoenix dactylifera) – 2.95%
* All other species combined comprise 35.35% of the total tree population analyzed.
Tree Diversity in Las Vegas, NV
The dataset for Las Vegas reveals the dominance of two tree species, the Afghan Pine (Pinus brutia) and Velvet Ash (Fraxinus velutina), which account for 18.48% and 14.06% of the total tree population, respectively.
The number of unique species identified among the 31,864 trees analyzed was 123, and the effective species number was 26.53. This means that tree diversity in Las Vegas is tantamount to having 27 species of trees in equal numbers. This relatively low number of effective species is further emphasized by the fact that the top ten most commonly observed trees make up almost two-thirds of the total tree population.
The majority of the trees observed were introduced (non-native) and reflect species adapted to the city’s desert landscape. The interesting blend of species in the Las Vegas dataset adds to the visual appeal and functionality of the city’s landscape while highlighting the challenge of achieving, and maintaining a diverse urban canopy in an arid, desert environment.
Common Trees in Los Angeles, California
With a population of over 3.8 million, Los Angeles, California, is known for its iconic palm trees and diverse urban forest.
Initiatives, such as City Plants, educate and train volunteers to become block leaders, host a tree adoption, and even offer free shade trees for the street or yard. Each household can apply for up to 7 free trees.
We analyzed the data on 574,282 trees currently growing in Los Angeles, CA, to see which are the most common species found in the city and how diverse they are.
Top 10 Most Common Trees Observed in Los Angeles, CA
- Mexican fan palm (Washingtonia robusta) – 6.61%
- Crape myrtle (Lagerstroemia indica) – 6.05%
- Southern magnolia (Magnolia grandiflora) – 5.40%
- American sweetgum (Liquidambar styraciflua) – 5.23%
- Indian laurel fig (Ficus microcarpa) – 4.99%
- London plane (Platanus acerifolia) – 3.04%
- Camphor tree (Cinnamomum camphora) – 2.76%
- Italian cypress (Cupressus sempervirens) – 2.45%
- Jacaranda (Jacaranda acutifolia) – 2.40%
- Carrotwood (Cupaniopsis anacardioides) – 2.04%
* All other species combined comprise 59.03% of the total tree population analyzed.
Tree Diversity in Los Angeles, CA
The dataset for Los Angeles suggests that the city’s urban forest is largely comprised of a wide variety of introduced tree species.
Out of 574,282 trees observed, 455,752 (nearly 80%) were categorized as introduced (non-native), and 531 unique species were identified. The effective species number was calculated to be 75.85, which means tree diversity in Los Angeles is akin to having 76 species in equal numbers.
The dominant species observed was the non-native Mexican Fan Palm (Washingtonia robusta), accounting for 6.61% of the total tree population. This was closely followed by the Crape Myrtle (Lagerstroemia indica) at 6.05%.
Other common species include the Southern Magnolia (5.40%), American Sweetgum (5.23%), and Indian Laurel Fig (4.99%). The native tree species that was observed in the highest numbers was the Modesto Ash (Fraxinus velutina), which accounted for just 1.51% of the total tree population.
Overall, Los Angeles’s urban forest showcases a diverse range of tree species. However, the dominance of introduced trees highlights the potential benefit of improving diversity by increasing the number of native plantings.
Common Trees in Louisville, Kentucky
Louisville City, Kentucky, has a population of over 240,000 (city only) and has been actively working to rebuild its tree canopy.
Initiatives like Louisville Grows, which has a goal of planting 1,000 trees each year, also educate the public on the benefits of an urban tree forest, planting trees, and ongoing maintenance.
If you live in the area, you can “adopt” up to 3 trees. Find out more about how to get your free trees here.
Another great initiative is Trees Louisville, which shows you how to get up to 2 free trees if you live in the area.
You can also host a neighborhood planting project, through which you can apply to have between 10 and 50 trees supplied free to be planted in the public right of way.
We analyzed the data on 32,711 trees currently growing in Louisville, KY, to see which are the most common species found in the city and how diverse the urban canopy is.
Top 10 Most Common Trees Observed in Louisville, KY
- Sugar maple (Acer saccharum) – 5.53%
- Pin oak (Quercus palustris) – 5.13%
- Red maple (Acer rubrum) – 4.70%
- Green ash (Fraxinus pennsylvanica) – 4.29%
- Common hackberry (Celtis occidentalis) – 3.32%
- Tulip poplar (Liriodendron tulipifera) – 3.05%
- Sweetgum (Liquidambar styraciflua) – 2.55%
- Northern red oak (Quercus rubra) – 2.46%
- American sycamore (Platanus occidentalis) – 2.45%
- White ash (Fraxinus americana) – 2.36%
* All other species combined comprise 64.15% of the total tree population analyzed.
Tree Diversity in Louisville, KY
The Louisville dataset included observations of 32,711 trees, and 234 unique species were identified. The effective species number was calculated to be 72.20, which means tree diversity in Louisville is tantamount to having an impressive 72 species in equal numbers.
The diversity of Louisville’s urban forest is further emphasized by the fact that the top ten most commonly observed trees only account for roughly 36% of the total tree population.
The most dominant species observed in Louisville was the native Sugar Maple (Acer saccharum), comprising 5.53% of the total tree population. Other dominant species include the native Pin Oak (Quercus palustris) and Red Maple (Acer rubrum), with native trees generally in greater abundance than introduced trees in Louisville (approximately 83% native, 13% introduced, and 4% uncategorized).
The data suggests that the urban forest in Louisville incorporates a diverse range of species, and the dominance of native species indicates a strong connection to the local ecosystem.
Common Trees in Madison, Wisconsin
Madison, Wisconsin, has a population of approximately 273,000, and the city’s Forestry Division is currently responsible for around 96,000 trees.
The Urban Tree Alliance organizes tree planning and planting and looks for local areas lacking in trees where planting them would benefit residents the most.
We analyzed the data on 95,779 trees currently growing in Madison, WI, to see which are the most common species found in the city.
Top 10 Most Common Trees Observed in Madison, WI
- Norway maple (Acer platanoides) – 21.8%
- Green ash (Fraxinus pennsylvanica) – 18.1%
- Honeylocust var. (Gleditsia triacanthos) – 10.4%
- Linden (Tilia) – 5.2%
- Littleleaf linden (Tilia cordata) – 4.1%
- Honeylocust (Gleditsia triacanthos) – 3.5%
- White ash (Fraxinus americana) – 3.1%
- American basswood (Tilia americana) – 3.1%
- Hackberry (Celtis occidentalis) – 2.8%
- Freeman maple (Acer freemanii) – 2.3%
* All other species combined comprise 25.6% of the total tree population analyzed.
Tree Diversity in Madison, WI
The dataset for Madison included observations on 95,779 trees, and 121 unique species were identified among those. The effective species number was calculated to be 13.61, which means tree diversity in the city is equivalent to having just 14 species in equal numbers.
This lack of diversity is highlighted by the strong dominance of three species of trees. The most dominant species by far was the Norway Maple (Acer platanoides), accounting for 21.8% of the total tree population. This is followed by Green Ash (Fraxinus pennsylvanica) and Honeylocust (Gleditsia triacanthos), which comprise 18.1% and 10.4% of the total tree population, respectively.
Additionally, the top ten most commonly observed trees in Madison account for almost 75% of the entire tree population observed, further demonstrating the limited diversity of species that make up the city’s urban forest.
Common Trees in Milwaukee, Wisconsin
With a population of approximately 563,000, Milwaukee is the largest city in Wisconsin and is located on the shores of Lake Michigan.
The Forestry services are responsible for managing roughly 200,000 street trees and are also educating residents on how to take action against the Emerald Ash Borer Beetle.
There are several great tree-planting initiatives active in Milwaukee aiming to boost urban canopy cover. Park People provide an opportunity to “Adopt-a-Tree” for yourself or somebody else, which is a great way to support the local community and wildlife.
Milwaukee Urban Forestry Fund is looking for people who want to organize a tree planting project (minimum ten trees), and Branch Out Milwaukee completed its Sherman Park Urban Forestry Grant pilot program.
We analyzed the data on 11,158 trees currently growing in Milwaukee, WI, to see which are the most common species found in the city and how diverse the city’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Milwaukee, WI
- Honeylocust (Gleditsia triacanthos) – 12.65%
- Green ash (Fraxinus pennsylvanica) – 12.15%
- Norway maple (Acer platanoides) – 8.17%
- Sugar maple (Acer saccharum) – 7.53%
- Common hackberry (Celtis occidentalis) – 6.27%
- Red oak (Quercus rubra) – 5.69%
- Hawthorn (Crataegus) – 5.23%
- White ash (Fraxinus americana) – 4.07%
- American (basswood) linden (Tilia americana) – 3.80%
- Crabapple (Malus tschonoskii) – 3.55%
* All other species combined comprise 30.88% of the total tree population analyzed.
Tree Diversity in Milwaukee, WI
Out of 11,158 trees observed in Milwaukee, 103 unique species were identified, and the effective species number was calculated to be 27.26. This means that tree diversity in the city is akin to having 27 species of trees in equal numbers.
The dominant tree species observed in Milwaukee were the Honeylocust (Gleditsia triacanthos) and Green Ash (Fraxinus pennsylvanica), each accounting for just over 12% of the total tree population observed.
Other prevalent species included the Norway Maple (Acer platanoides), Sugar Maple (Acer saccharum), and Common Hackberry (Celtis occidentalis), with the top ten most commonly observed trees accounting for almost 70% of the total tree population.
The dominance of a few species of trees, combined with the uneven distribution among species, indicates a potential for improving the species diversity of the urban forest in Milwaukee.
Common Trees in Minneapolis, Minnesota
Minneapolis, Minnesota, has a population of approximately 425,000, and the city’s tree canopy covers more than 29.8% of its area.
Residents can request a free tree, and businesses can apply for a low-cost tree through the local City Trees program.
City and Minneapolis Park and Recreation Board officials announced the goal of planting 200,000 trees by 2040. Superintendent Bangoura advised that the initial plan was to plant 18,000 trees in 2023 and 2024, focusing on Green Zones.
We analyzed the data on 176,834 trees currently growing in Minneapolis, MN, to see which are the most common species found in the city and how diverse the city’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Minneapolis, MN
- Green Ash (Fraxinus pennsylvanica) – 15.95%
- Norway Maple (Acer platanoides) – 11.42%
- American Elm (Ulmus americana) – 9.18%
- Sugar Maple (Acer saccharum) – 8.69%
- American Linden (Tilia americana) – 7.21%
- Hackberry (Celtis occidentalis) – 7.20%
- Little-leaf Linden (Tilia cordata) – 7.17%
- Honeylocust (Gleditsia triacanthos) – 7.17%
- Red Maple (Acer rubrum) – 2.37%
- Elm (Ulmus) – 2.26%
* All other species combined comprise 21.38% of the total tree population analyzed.
Tree Diversity in Minneapolis, MN
With 136 unique species identified in the Minneapolis dataset of 176,834 trees, the effective species number was calculated to be 19.84. This means tree diversity in the city is equivalent to having just 20 species in equal numbers.
The dominant species observed in Minneapolis was the Green Ash (Fraxinus pennsylvanica), accounting for 15.95% of the total tree population. Other dominant species included the Norway Maple (Acer platanoides) and American Elm (Ulmus americana), and the top ten most commonly observed trees accounted for almost 80% of the entire tree population surveyed in Minneapolis.
At least 66% of the trees observed were categorized as native, almost 27% were introduced (non-native), and the remaining 7% were uncategorized.
The dominance of a few species and the uneven distribution among species indicate potential for improved tree diversification in Minneapolis.
Common Trees in Nashville, Tennessee
Nashville, Tennessee, has a population of approximately 683,000, and between 2008 and 2016, its tree canopy fell in urban zones by 15%.
The City of Nashville has an ambitious target to plant 500,000 trees by 2050, and the Root Nashville public and private campaign provides opportunities for residents to get free trees for their yards. They are also offering 10+ trees for businesses and places of worship.
Other local initiatives, such as the Nashville Tree Foundation, are doing great work planting, preserving, and educating about trees.
We analyzed the data on 2,059 trees currently growing in Nashville, TN, to see which are the most common species found in the city and how diverse Nashville’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Nashville, TN
- London planetree (Platanus acerifolia) – 13.65%
- Japanese zelkova (Zelkova serrata) – 8.06%
- Willow oak (Quercus phellos) – 7.48%
- Sweetgum (Liquidambar styraciflua) – 6.36%
- Lacebark elm (Ulmus parvifolia) – 5.83%
- Yoshino cherry (Prunus yedoensis) – 4.81%
- Ginkgo (Ginkgo biloba) – 4.32%
- Siberian elm (Ulmus pumila) – 4.08%
- River birch (Betula nigra) – 3.93%
- Shumard oak (Quercus shumardii) – 3.74%
* All other species combined comprise 37.74% of the total tree population analyzed.
Tree Diversity in Nashville, TN
The Nashville dataset contained information on a relatively small number of trees (2,059); among those, 57 unique species were identified. The effective species number calculation for Nashville is 26.17, which means tree diversity in Nashville is akin to having 26 species in equal numbers.
The dominant species observed was the London Planetree (Platanus acerifolia), accounting for 13.65% of the total tree population and significantly outnumbering other species.
Japanese Zelkova (Zelkova serrata), Willow Oak (Quercus phellos), and Sweetgum (Liquidambar styraciflua) were among the other most common trees observed in Nashville. The top ten most commonly observed trees account for over 62% of the entire population.
The data suggests that Nashville’s urban forest consists of a blend of native and introduced species, creating visual appeal and ecological functionality. However, the dominance of a few species, combined with the uneven distribution among species, indicates a potential for improving species diversity in Nashville.
Common Trees in New Berlin, Wisconsin
New Berlin, Wisconsin, has a population of approximately 40,000.
While no local tree planting initiatives could be identified, Governor Tony Evers of Wisconsin has pledged to conserve 125,000 acres of forestland, plant 74 million trees in rural areas, and plant 1 million trees in urban areas.
We analyzed the data on 6,270 trees currently growing in New Berlin, WI, to see which are the most common species found in the city and how diverse the urban canopy is.
Here are the results!
Top 10 Most Common Trees Observed in New Berlin, WI
- Green ash (Fraxinus pennsylvanica) – 10.19%
- Blue spruce (Picea pungens) – 9.78%
- Norway maple (Acer platanoides) – 7.62%
- White ash (Fraxinus americana) – 4.78%
- Honeylocust (Gleditsia triacanthos) – 4.55%
- Crabapple (Malus tschonoskii) – 4.29%
- American (basswood) linden (Tilia americana) – 3.80%
- Elm (Ulmus) – 2.89%
- White oak (Quercus alba) – 2.71%
- Shagbark hickory (Carya ovata) – 2.54%
* All other species combined comprise 46.86% of the total tree population analyzed.
Tree Diversity in New Berlin, WI
The data suggests that New Berlin has a reasonably diverse urban forest with 108 unique tree species observed in this analysis of 6,270 trees.
The dominant species observed was the Green Ash (Fraxinus pennsylvanica), accounting for 10.19% of the total tree population observed, and closely followed by the Blue Spruce (Picea pungens) at 9.78%.
The effective species number for New Berlin was calculated to be 39.34, which means tree diversity in the city is akin to having 39 species in equal numbers. This data indicates potential for improved diversity among tree species in New Berlin.
Common Trees in New Orleans, Louisiana
New Orleans, Louisiana, has a population of approximately 370,000. In 2005, the city tragically lost an estimated 200,000 trees to Hurricane Katrina.
New Orleans currently has an urban tree canopy of 18.5% and aims to increase it to 24% by 2040. According to Soul Nola and their reforestation plan, it will require a total of 100,000 trees – roughly 7,000 trees per year for the next 15 years.
The Nola Tree Project is also doing its part to help the effort.
We analyzed the data on 104,099 trees currently growing in New Orleans, LA, to see which are the most common species found in the city and how diverse the urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in New Orleans, LA
- Crape myrtle (Lagerstroemia indica) – 29.1%
- Southern live oak (Quercus virginiana) – 20.9%
- Bald cypress (Taxodium distichum) – 5.2%
- Hybrid holly species (Ilex attenuata) – 3.4%
- Slash pine (Pinus elliottii) – 3.0%
- Southern magnolia (Magnolia grandiflora) – 2.9%
- Ornamental pear (Pyrus calleryana) – 1.9%
- Palmetto (Sabal palmetto) – 1.9%
- Chinese elm (Ulmus parvifolia) – 1.8%
- Sweetbay magnolia (Magnolia virginiana) – 1.7%
* All other species combined comprise 28.2% of the total tree population analyzed.
Tree Diversity in New Orleans, LA
New Orleans boasts 320 unique tree species, as observed in this dataset of 104,099 trees. However, we calculated the effective species number to be 20.13, which means tree diversity in the city is akin to having just 20 species of trees evenly distributed.
Two species were overwhelmingly dominant, the Crape Myrtle (Lagerstroemia indica) accounting for almost 30% of the total population of trees observed, and the Southern Live Oak (Quercus virginiana) comprising 20.9%.
These two species significantly outnumbered all others and combined account for approximately 50% of the entire tree population observed in New Orleans.
The presence of iconic species such as the Southern Live Oak and Bald Cypress are emblematic of the city’s natural heritage, and the urban forest in New Orleans reflects a balanced presence of native and non-native trees.
However, the dominance of a certain species, combined with the uneven distribution among all species, indicates a need for further diversification of urban tree cover in New Orleans.
Common Trees in New York City, New York
New York City has a population of over 8.3 million and is home to approximately 5.2 million trees.
Tree planting initiatives include Trees New York, an organization that plants, preserves, and protects the city’s urban forest. NYC Parks website enables free trees to be requested to be planted in your street.
The original Million Trees NYC initiative was a success, and in 2022, the city’s five borough presidents met with Mayor Eric Adams and pushed to revive the Million Trees initiative and aim to plant a million new trees by 2030.
We analyzed the data on 652,169 trees currently growing in New York City, NY, to see which are the most common species found in the city and how diverse they are.
Here are the results!
Top 10 Most Common Trees Observed in New York City, NY
- London planetree (Platanus acerifolia) – 13.34%
- Honeylocust (Gleditsia triacanthos) – 9.85%
- Callery pear (Pyrus calleryana) – 9.04%
- Pin oak (Quercus palustris) – 8.16%
- Norway maple (Acer platanoides) – 5.24%
- Littleleaf linden (Tilia cordata) – 4.56%
- Cherry (Prunus) – 4.49%
- Japanese zelkova (Zelkova serrata) – 4.49%
- Ginkgo (Ginkgo biloba) – 3.22%
- Sophora (Styphnolobium japonicum) – 2.97%
* All other species combined comprise 34.65% of the total tree population analyzed.
Tree Diversity in New York City, NY
A large dataset of 652,169 trees was observed in New York, with 131 unique species identified. The effective species number was calculated to be 29.76, which means tree diversity in the city is akin to having just 30 species of trees in equal numbers.
London Planetree (Platanus acerifolia) accounted for 13.34% of the total tree population, significantly outnumbering other species. Other prevalent species included the Honeylocust (Gleditsia triacanthos), Callery Pear (Pyrus calleryana), and Pin Oak (Quercus palustris).
The top ten most commonly observed trees account for 65.35% of the total tree population in New York.
Overall, New York’s urban forest reflects a reasonably diverse variety of species, with a significant emphasis on introduced trees (over 64%). The dominance of certain species and uneven distribution among all species indicates a potential for improved species diversity in New York, particularly among the native tree population.
Common Trees in Oakland, California
Oakland, California, has a population of approximately 430,000, and its urban tree canopy coverage currently sits at 21.5%.
Initiatives such as Trees for Oakland are helping by planting and maintaining trees and educating locals about their importance. Oakland Parks has also committed to planting 2,000 trees in East Oakland by the end of 2024.
We analyzed the data on 35,568 trees currently growing in Oakland, CA, to see which are the most common species found in the city and how diverse Oakland’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Oakland, CA
- London Plane (Platanus acerifolia) – 10.65%
- Sweetgum (Liquidambar styraciflua) – 9.31%
- Cherry (Prunus L.) – 8.24%
- Callery Pear (Pyrus calleryana) – 7.54%
- Ash (Fraxinus) – 6.08%
- Crape Myrtle (Lagerstroemia indica) – 5.49%
- Evergreen Pear (Pyrus kawakamii) – 4.01%
- Southern Magnolia (Magnolia grandiflora) – 3.87%
- Chinese Pistache (Pistacia chinensis) – 3.23%
- Maple (Acer L.) – 2.73%
* All other species combined comprise 38.85% of the total tree population analyzed.
Tree Diversity in Oakland, CA
Out of the 35,568 trees observed in Oakland, over 64% were categorized as non-native, and 180 unique species were identified.
The effective species number was calculated to be 40.21, meaning tree diversity in Oakland is tantamount to having 40 species of trees in equal numbers.
The London Plane (Platanus acerifolia) was the most dominant species observed, accounting for 10.65% of the total tree population.
Other commonly observed species included Sweetgum (Liquidambar styraciflua), Cherry (Prunus L.), and Callery Pear (Pyrus calleryana), and the top ten most common tree species accounted for over 60% of the total tree population.
This data suggests that Oakland’s urban forest comprises a reasonably diverse mix of tree species, with a significant emphasis on introduced species. The dominance of certain species and uneven distribution among the observed species indicates the potential for further diversification of tree species contributing to Oakland’s urban canopy cover.
Common Trees in Oklahoma City, Oklahoma
Oklahoma City, the capital of Oklahoma, has a population of approximately 695,000 and an estimated 21.4% canopy cover.
Tree OKC was created to expand tree canopy throughout the metro area through education, tree plantings, and more.
Free trees are available for all homes and businesses if you live in a Strong Neighborhoods Initiative area.
We analyzed the data on 9,730 trees currently growing in Oklahoma City, OK, to see which are the most common species found in the city and how diverse they are.
Here are the results!
Top 10 Most Common Trees Observed in Oklahoma City, OK
- Eastern redcedar (Juniperus virginiana) – 7.31%
- Common crapemyrtle (Lagerstroemia indica) – 7.08%
- Post oak (Quercus stellata) – 6.00%
- Chinese pistache (Pistacia chinensis) – 5.83%
- Chinese elm (Ulmus parvifolia) – 4.68%
- Austrian pine (Pinus nigra) – 4.66%
- Shumard oak (Quercus shumardii) – 3.94%
- Common baldcypress (Taxodium distichum) – 3.87%
- Siberian elm (Ulmus pumila) – 3.36%
- Blackjack oak (Quercus marilandica) – 3.32%
* All other species combined comprise 49.96% of the total tree population analyzed.
Tree Diversity in Oklahoma City, OK
The Oklahoma dataset included observations on 9,730 trees, and 98 unique species were identified. The effective species number was calculated to be 28.20, which means tree diversity in the city is equivalent to having just 28 species in equal numbers.
The urban forest in Oklahoma is characterized by a mix of native species, such as the Eastern Redcedar (Juniperus virginiana) and Post Oak (Lagerstroemia indica), along with introduced (non-native) trees including the Common Crapemyrtle (Lagerstroemia indica) and Chinese Pistache (Pistacia chinensis).
The presence of native species suggests that Oklahoma’s urban forest has a connection to the region’s natural heritage. In contrast, the addition of introduced species adds to the adaptability and aesthetic diversity of the city’s urban canopy.
Common Trees in Ontario, California
Ontario City, California, has a population of approximately 180,000.
No local tree-planting initiatives were identified in Ontario City. However, California Releaf is a state-wide initiative that partners with communities to increase and protect urban and community forests.
We analyzed the data on 58,577 trees currently growing in Ontario, CA, to see which are the most common species found in the city and how diverse Ontario’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Ontario, CA
- Crape myrtle (Lagerstroemia indica) – 7.90%
- American sweetgum (Liquidambar styraciflua) – 7.50%
- Camphor tree (Cinnamomum camphora) – 6.66%
- Canary Island pine (Pinus canariensis) – 5.65%
- London plane (Platanus acerifolia) – 5.24%
- Ornamental pear (Pyrus calleryana) – 4.77%
- Queen palm (Syagrus romanzoffiana) – 3.60%
- Mexican fan palm (Washingtonia robusta) – 2.70%
- Chinese pistache (Pistacia chinensis) – 2.29%
- California pepper (Schinus molle) – 2.09%
* All other species combined comprise 51.61% of the total tree population analyzed.
Tree Diversity in Ontario, CA
Ontario boasts 239 unique tree species and 52.93 effective species, as observed in this dataset of 58,577 trees. This means that tree diversity in Ontario is akin to having 53 species in equal numbers.
The most dominant species observed were largely categorized as introduced (non-native) and included the Crape Myrtle (Lagerstroemia indica), American Sweetgum (Liquidambar styraciflua), and Camphor Tree (Cinnamomum camphora). Introduced species accounted for at least 86% of the total tree population in Ontario.
These species are well adapted to the unique Ontario climate and contribute to the visual appeal of the city’s landscape. However, Ontario’s urban forest has a significant emphasis on introduced species.
While tree species in Ontario are reasonably diverse, the dominance of certain species, uneven distribution among species, and the strong presence of introduced species indicate a potential for improved species diversification in Ontario.
Common Trees in Orlando, Florida
Orlando, Florida, has a population of over 316,000 and is actively working to enhance its urban tree cover.
The “Energy Saving Trees” initiative enables residents to request free street trees, as well as free trees for their private yards. The program aims to educate citizens on reducing energy costs by strategically planting trees on their property.
We analyzed the data on 68,211 trees currently growing in Orlando, FL, to see which are the most common species found in the city and how diverse Orlando’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Orlando, FL
- Live oak (Quercus virginiana) – 25.11%
- Common crapemyrtle (Lagerstroemia indica) – 21.97%
- Laurel oak (Quercus laurifolia) – 15.57%
- Cabbage palmetto (Sabal palmetto) – 4.19%
- Chinese elm (Ulmus parvifolia) – 3.82%
- Southern magnolia (Magnolia grandiflora) – 2.86%
- Red maple (Acer rubrum) – 2.66%
- Holly (Ilex) – 2.48%
- Shumard oak (Quercus shumardii) – 2.06%
- Mexican fan palm (Washingtonia robusta) – 2.03%
* All other species combined comprise 17.25% of the total tree population analyzed.
Tree Diversity in Orlando, FL
The Orlando dataset included observations on 68,211 trees, and 158 unique species were identified. The effective species number was calculated to be 12.03, which means tree diversity in Orlando is akin to having just 12 different species of trees in equal numbers.
While the urban canopy in Orlando comprises a relatively balanced mix of native and non-native species, the dominance of certain species and uneven distribution among species indicate a need for improved species diversification in Orlando.
Two species, the native Live Oak (Quercus virginiana) and non-native Common Crapemyrtle (Lagerstroemia indica), combined account for a huge 47.08% of the total tree population observed.
The lack of species diversity in Orlando is further evidenced by the fact that the ten most commonly observed trees account for 82.75% of the entire population of trees observed in the city.
While the mix of species observed contributes to the city’s unique landscape and cultural identity, the data suggests that further diversification of Orlando’s urban forest would be beneficial.
Common Trees in Overland Park, Kansas
Overland Park, Kansas, has a population of approximately 200,000, and the city recognizes trees as a vital community asset.
Through the ‘Contain The Rain’ program, homeowners and businesses are able to purchase native trees and receive up to 50% reimbursement.
We analyzed the data on 44,767 trees currently growing in Overland Park, KS, to see which are the most common species found in the city and how diverse the urban canopy is.
Here are the results!
Top 10 Most Common Trees Observed in Overland Park, KS
- Red maple (Acer rubrum) – 29.68%
- White ash (Fraxinus americana) – 17.10%
- Pin oak (Quercus palustris) – 7.64%
- Sweetgum (Liquidambar styraciflua) – 4.43%
- Green ash (Fraxinus pennsylvanica) – 4.31%
- Crabapple (Malus) – 3.16%
- Callery pear (Pyrus calleryana) – 3.03%
- Silver maple (Acer saccharinum) – 2.71%
- Honeylocust (Gleditsia triacanthos) – 2.06%
- Littleleaf linden (Tilia cordata) – 2.01%
* All other species combined comprise 23.88% of the total tree population analyzed.
Tree Diversity in Overland Park, KS
Of the 44,767 trees observed in Overland Park, 51% were categorized as native, and 139 unique species were identified. The effective species number was calculated to be 16.95, which means tree diversity in Overland Park is equivalent to having just 17 species of trees in equal numbers.
Over 76% of the total tree population observed was comprised of just ten trees, and the most dominant species, the Red Maple (Acer rubrum), accounted for a large 29.68% of the total tree population. White Ash is also a dominant species observed in Overland Park, comprising 17.10% of the tree population.
Although the urban forest in Overland Park showcases a balanced mix of native and introduced (non-native) species, the overwhelming dominance of certain species and uneven distribution among species indicate a potential for improved species diversity in the city.
Common Trees in Pittsburgh, Pennsylvania
Pittsburgh, Pennsylvania, has a population of approximately 300,000, and when it comes to trees, Tree Pittsburgh is the premier resource.
Tree Pittsburgh’s initiative, The Giving Grove, supports neighborhood volunteers in planting and caring for nut trees, fruit trees, and berry brambles.
Tree Adoptions are also popular and enable locals to adopt a tree (or two) for their yard, which must be planted on private property.
For street trees, residents can request to have a free tree planted outside their property; however, certain conditions need to be met to be eligible.
We analyzed the data on 40,158 trees currently growing in Pittsburgh, PA, to see which are the most common species found in the city and how diverse Pittsburgh’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Pittsburgh, PA
- Norway maple (Acer platanoides) – 9.25%
- Red maple (Acer rubrum) – 8.52%
- London planetree (Platanus acerifolia) – 8.06%
- Callery pear (Pyrus calleryana) – 7.39%
- Littleleaf linden (Tilia cordata) – 6.01%
- Thornless honeylocust (Gleditsia triacanthos) – 5.03%
- Pin oak (Quercus palustris) – 4.16%
- Flowering crabapple (Malus) – 3.26%
- Ginkgo (Ginkgo biloba) – 3.03%
- Northern red oak (Quercus rubra) – 2.44%
* All other species combined comprise 42.84% of the total tree population analyzed.
Tree Diversity in Pittsburgh, PA
Pittsburgh has a diverse urban forest with 222 unique tree species observed in this analysis. The effective species number was calculated to be 42.23, which means tree diversity in the city is akin to having 42 species of trees in equal numbers.
The data suggests there is a good balance of native and non-native species that make up Pittsburgh’s urban forest. The introduced (non-native) Norway maple (Acer platanoides) accounts for 9.25% of the tree population, outnumbering other species.
Red maple (Acer rubrum), London planetree (Platanus acerifolia), and Callery pear (Pyrus calleryana) are among the other most common tree species observed in Pittsburgh.
The mix of tree species identified in Pittsburgh contribute to the visual appeal, ecological functionality, and cultural identity of the city’s landscape.
Common Trees in Plano, Texas
Plano, Texas, has a population of approximately 290,000, and its overall urban tree canopy sits at 21%, according to the Plano Urban Forest Master Plan.
‘Live Green in Plano’ holds Tree Giveaways to help increase Plano’s tree canopy. You can find out more information about this initiative on the Plano Gov website.
We analyzed the data on 28,290 trees currently growing in Plano, TX, to see which are the most common species found in the city and how diverse Plano’s urban canopy is.
Here are the results!
Top 10 Most Common Trees Observed in Plano, TX
- Cedar elm (Ulmus crassifolia): 12.87%
- Common hackberry (Celtis occidentalis): 11.59%
- Crape myrtle (Lagerstroemia indica): 9.82%
- Red oak (Quercus rubra): 9.18%
- Live oak (Quercus virginiana): 6.74%
- Bald cypress (Taxodium distichum): 5.65%
- Pecan (Carya illinoinensis): 4.40%
- Ash (Fraxinus): 4.27%
- Chinese pistache (Pistacia chinensis): 2.91%
- Bradford pear (Pyrus calleryana): 2.88%
* All other species combined comprise 29.69% of the total tree population analyzed.
Tree Diversity in Plano, TX
The Plano dataset included observations on 28,290 trees, and 86 unique species were identified among those. The effective species number was calculated to be 12.88, which means tree diversity in the city is tantamount to having just 13 species in equal numbers.
Plano’s urban forest reflects a strong presence of native species, with 64% of the trees observed characterized as native. The most dominant species of trees observed in Plano were the native Cedar Elm (Ulmus crassifolia), Common Hackberry (Celtis occidentalis), Red Oak (Quercus rubra), and Live Oak (Quercus virginiana), accounting for 12.87%, 11.59%, 9.18% and 6.74% of the total tree population, respectively.
The Crape Myrtle (Lagerstroemia indica) was the most dominant introduced (non-native) species observed, comprising 9.82% of the total tree population.
Overall, Plano’s urban forest is comprised of a diverse array of species with a mix of native and introduced trees. However, the dominance of certain species, combined with the uneven distribution among species, indicates potential for improving species diversity in Plano.
Common Trees in Portland, Oregon
Portland is Oregon’s largest city and has a population of around 635,000.
The city has some great initiatives that include a yard tree giveaway (2 free yard trees) and street tree planting, where they choose neighborhoods with a high need for tree canopy and plant more trees in those.
Other tree planting initiatives in Orlando include Trees for Schools, Free Trees for Commercial and Industrial properties, and Treebate and Clean River Rewards.
We analyzed the data on 216,751 trees currently growing in Portland, OR, to see which are the most common species found in the city and how diverse they are.
Here are the results!
Top 10 Most Common Trees Observed in Portland, OR
- Norway maple (Acer platanoides) – 8.86%
- Red maple (Acer rubrum) – 7.14%
- Cherry (Prunus) – 6.31%
- Pear (Pyrus) – 5.40%
- Plum (Prunus) – 5.28%
- Other maple (Acer) – 4.91%
- Ash (Fraxinus) – 4.29%
- Dogwood (Cornus) – 4.00%
- Deciduous oak (Quercus) – 3.26%
- Crabapple (Malus) – 3.13%
* All other species combined comprise 47.43% of the total tree population analyzed.
Tree Diversity in Portland, OR
Observations on a total of 216,751 trees were included in the Portland dataset, and out of those, 157 unique tree species were identified. The effective species number was calculated to be 38.34, which means tree diversity in Portland is akin to having 38 species in equal numbers.
The dominant species observed was the Norway Maple (Acer platanoides), which accounted for 8.86% of the total tree population observed. Other common tree species in Portland include the Red Maple (Acer rubrum), Cherry trees (Prunus spp.), and Pear trees (Pyrus spp.).
The dataset indicates that the urban forest in Portland comprises a diverse array of species with a blend of introduced and native trees, all contributing to the visual appeal and ecological functionality of the city’s landscape.
Common Trees in Providence, Rhode Island
Providence, the capital city of Rhode Island, has a population of around 190,000 and currently has an urban tree canopy coverage of 23%.
Initiatives like the Providence Neighborhood Planting Program (PNPP) enables residents and business owners to apply for 5-25 free street trees. This is in exchange for helping to plant and care for the young trees.
Residents in East Providence can apply for a free tree via Groundwork Rhode Island. Successful applicants are responsible for watering the tree for the first 2-3 years.
We analyzed the data on 24,082 trees currently growing in Providence, RI, to see which are the most common species found in the city and how diverse the city’s urban canopy is.
Here are the results!
Top 10 Most Common Trees Observed in Providence, RI
- Norway Maple (Acer platanoides) – 12.68%
- Callery Pear (Pyrus calleryana) – 11.59%
- Honey Locust (Gleditsia triacanthos) – 8.51%
- London Plane (Platanus acerifolia) – 7.75%
- Green Ash (Fraxinus pennsylvanica) – 7.12%
- Red Maple (Acer rubrum) – 5.85%
- Japanese Zelkova (Zelkova serrata) – 4.95%
- Little-leaf Linden (Tilia cordata) – 4.09%
- Pin Oak (Quercus palustris) – 2.67%
- Cherry (Prunus) – 2.38%
* All other species combined comprise 32.40% of the total tree population analyzed.
Tree Diversity in Providence, RI
The Providence dataset included observations on 24,082 trees, and 119 unique species were identified among those. The effective species number was calculated to be 28.55, which means tree diversity in the city is equivalent to having 29 species of trees in equal numbers.
The dataset reflects a higher presence of introduced (non-native) species, with at least 61% of the trees categorized as introduced. The dominant introduced species include the Norway Maple (Acer platanoides), Callery Pear (Pyrus calleryana), Honey Locust (Gleditsia triacanthos), and London Plane (Platanus acerifolia) each accounting for 12.68%, 11.59%, 8.51% and 7.75% of the total tree population, respectively.
The most dominant native species, comprising 7.12% of the total population, was the Green Ash (Fraxinus pennsylvanica), followed by the Red Maple (Acer rubrum) and Pin Oak (Quercus palustris).
This data suggests that Providence’s urban forest is made up of a rich blend of both native and introduced species, contributing to the city’s visual appeal and ecological integrity. However, the dominance of certain species combined with the uneven distribution among species indicates potential for improved species diversity in Providence.
Common Trees in Rancho Cucamonga, California
Rancho Cucamonga, California, has a population of approximately 175,000 and is currently working on its first Urban Forest Management Plan (UFMP).
While we couldn’t find any active tree planting initiatives, the community can offer input via this survey, indicating what they believe is important to consider in the UFMP.
We analyzed the data on 80,471 trees currently growing in Rancho Cucamonga, CA, to see which are the most common species found in the city and how diverse the urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Rancho Cucamonga, CA
- Crape myrtle (Lagerstroemia indica) – 15.90%
- Sycamore (Platanus acerifolia) – 7.07%
- Southern blue gum (Eucalyptus globulus) – 6.87%
- Magnolia (Magnolia grandiflora) – 6.20%
- Callery pear (Pyrus calleryana) – 6.14%
- Liquidambar (Liquidambar styraciflua) – 4.62%
- Pine (Pinus) – 4.60%
- Kurrajong (Brachychiton populneus) – 4.51%
- Chinese pistache (Pistacia chinensis) – 3.99%
- Canary Island pine (Pinus canariensis) – 2.93%
* All other species combined comprise 37.17% of the total tree population analyzed.
Tree Diversity in Rancho Cucamonga, CA
Of the 80,471 trees observed in Rancho Cucamonga, nearly 84% were categorized as introduced (non-native), and only 1.4% were categorized as native, with the remaining trees left uncategorized. The number of unique species identified was 199, and the effective species calculation was 31.67. This means tree diversity in Rancho Cucamonga is akin to having 32 species of trees in equal numbers.
The dominant species observed was the Crape Myrtle (Lagerstroemia indica), accounting for 15.9% of the total tree population observed. Other commonly observed trees included the Sycamore (Platanus acerifolia), Southern Blue Gum (Eucalyptus globulus), and Magnolia (Magnolia grandiflora).
This data indicates that Rancho Cucamonga’s urban forest showcases a diverse array of species, contributing to the city’s aesthetic appeal and ecological sustainability. However, the strong presence of introduced species and the dominance of certain species indicate a potential for improved tree diversity in Rancho Cucamonga, particularly among the native tree population.
Common Trees in Richmond, Virginia
Richmond, the capital of Virginia, has a population of approximately 230,000, and the local Urban Forestry Division maintains around 120,000 trees.
Initiatives such as Capital Trees, Richmond Tree Stewards, and Reforest Richmond are working to educate the public on the importance of trees, and some are partnering with volunteers and donors to plant as many trees as possible.
We analyzed the data on 1815 trees currently growing in Richmond, VA, to see which are the most common species found in the city and how diverse Richmond’s urban canopy is.
Here are the results!
Top 10 Most Common Trees Observed in Richmond, VA
- Sugar Maple (Acer saccharum) – 12.51%
- Willow Oak (Quercus phellos) – 9.42%
- Common Crapemyrtle (Lagerstroemia indica) – 8.87%
- Red Maple (Acer rubrum) – 8.15%
- Pin Oak (Quercus palustris) – 7.33%
- Japanese Zelkova (Zelkova serrata) – 7.11%
- Winged Elm (Ulmus alata) – 4.35%
- Green Ash (Fraxinus pennsylvanica) – 2.92%
- Callery Pear (Pyrus calleryana) – 2.53%
- Hedge Maple (Acer campestre) – 2.48%
* All other species combined comprise 34.33% of the total tree population analyzed.
Tree Diversity in Richmond, VA
The dataset for Richmond contained a relatively small sample of just 1815 trees; however, some insight into tree diversity can be obtained from the data.
A total of 80 unique species were identified, and at least 63% of these were categorized as native. Among the dominant native species were the Sugar Maple (Acer saccharum), Willow Oak (Quercus phellos), Red Maple (Acer rubrum), and Pin Oak (Quercus palustris), each accounting for 12.51%, 9.42%, 8.15% and 7.33% of the total tree population, respectively.
The Common Crapemyrtle (Lagerstroemia indica) was the most dominant introduced species, comprising 8.87% of the observed tree population.
The effective species number for Richmond was calculated to be 28.08, which means tree diversity in the city is akin to having 28 different species of trees in equal numbers.
Overall, Richmond’s urban forest is characterized by a diverse array of species with a strong focus on native trees, suggesting a good connection to the local ecosystem. The uneven distribution among species and the dominance of certain species indicate that the city may benefit from further tree diversification to promote a healthy, sustainable urban forest.
Common Trees in Rochester, New York
Rochester, New York, is a city on Lake Ontario with a population of approximately 210,000.
In 2022, Rochester Mayor Malik Evans announced his goal was to plant 70,000 trees over the next four years, targeting neighborhoods that are lacking trees. This ambitious target may have been downgraded as this article suggests the target is to plant 6,000 trees by 2025.
There is a limited number of free trees residents and business owners can apply for via the Free Street Tree Program or Community Canopy Program.
We analyzed the data on 63,929 trees growing in Rochester, NY, to see which are the most common species observed in the city and how diverse the urban canopy is.
Here are the results!
Top 10 Most Common Trees Observed in Rochester, NY
- Norway maple (Acer platanoides) – 17.19%
- Honeylocust species (Gleditsia triacanthos) – 9.87%
- Little leaf linden (Tilia cordata) – 5.21%
- London planetree (Platanus acerifolia) – 4.65%
- Green ash (Fraxinus pennsylvanica) – 3.91%
- Japanese tree lilac (Syringa reticulata) – 3.50%
- Northern red oak (Quercus rubra) – 3.41%
- Pear species (Pyrus) – 3.09%
- Red maple (Acer rubrum) – 2.85%
- Crabapple species (Malus) – 2.53%
* All other species combined comprise 43.82% of the total tree population analyzed.
Tree Diversity in Rochester, NY
With 196 unique tree species identified in this analysis of 63,929 trees and an effective species number of 40.38, Rochester appears to have a reasonably diverse urban forest, akin to having 40 species of trees in equal numbers.
However, the dominance of certain species, in particular the Norway Maple (Acer platanoides), which accounts for 17.19% of the total tree population observed, and the uneven distribution among species does indicate that increased species diversity in Rochester may be needed.
The dataset reflects the presence of both native and introduced species contributing to urban canopy cover in Rochester, with introduced trees representing the more significant portion of the total tree population.
Common Trees in Sacramento, California
Sacramento, the capital of California, currently has a population of around 530,000.
The city is working to improve its canopy cover with initiatives like the Sacramento Tree Foundation, which is working with volunteers to educate people on how to plant and tend to trees within the city.
Customers of Sacramento Municipal Utility District (SMUD) can apply for up to 10 free shade trees delivered to their homes or businesses.
The city aims to plant 1,000 trees per planting season until they reach optimum stocking density.
We analyzed the data on 87,191 trees growing in Sacramento, CA, to see which are the most common species in the city and how diverse Sacramento’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Sacramento, CA
- London Planetree (Platanus acerifolia) – 16.18%
- Chinese Pistache (Pistacia chinensis) – 5.25%
- Callery Pear (Pyrus calleryana) – 4.91%
- Common Crapemyrtle (Lagerstroemia indica) – 4.76%
- Chinese Elm (Ulmus parvifolia) – 4.64%
- Japanese Zelkova (Zelkova serrata) – 4.43%
- California White Oak (Quercus lobata) – 4.24%
- Coast Redwood (Sequoia sempervirens) – 3.34%
- Modesto Ash (Fraxinus velutina) – 2.61%
- Sweetgum (Liquidambar styraciflua) – 2.22%
* All other species combined comprise 47.43% of the total tree population analyzed.
Tree Diversity in Sacramento, CA
The Sacramento dataset included observations on 87,191 trees, and 106 unique species were identified among those. The effective species number was calculated to be 34.53, which means tree diversity in the city is akin to having 35 species in equal numbers.
Introduced (non-native) species account for at least 72% of the total tree population, with the non-native London Planetree (Platanus acerifolia) comprising 16.18% of the total population and significantly outnumbering other species of trees in the dataset.
Other dominant species included the non-native Chinese Pistache (Pistacia chinensis), Callery Pear (Pyrus calleryana), Common Crapemyrtle (Lagerstroemia indica), and Chinese Elm (Ulmus parvifolia).
The data indicates that the urban forest in Sacramento is comprised of a diverse array of tree species, with a focus on introduced trees. The dominance of certain species, such as the London Planetree, combined with the uneven distribution among species, indicates potential for improved diversification, particularly by increasing the presence of native species.
Common Trees in San Diego, California
San Diego, California, has a population of approximately 1.38 million and is reported to have an urban tree canopy coverage of 13%.
According to San Diego’s climate action plan, the goal is to plant 40,000 new trees in communities by 2030 and 100,000 trees by 2035.
Initiatives such as Tree San Diego collaborates with government agencies, community, and business to plant the right trees in the right places. They are also instrumental in tree care, reforestation planning, community education, and more.
We analyzed the data on 212,237 trees currently growing in San Diego, CA, to see which are the most common species found in the city and how diverse the city’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in San Diego, CA
- Queen palm (Syagrus romanzoffianum) – 10.66%
- Carrot wood (Cupaniopsis anacardioides) – 6.41%
- Pine (Pinus) – 5.97%
- Eucalyptus (Eucalyptus) – 5.66%
- Mexican fan palm (Washingtonia robusta) – 5.46%
- Sweet gum (Liquidambar styraciflua) – 4.86%
- Jacaranda (Jacaranda acutifolia) – 4.63%
- Brisbane box (Lophostemon confertus) – 3.58%
- California sycamore (Platanus racemosa) – 3.45%
- African fern pine (Podocarpus gracilior) – 2.90%
* All other species combined comprise 46.4% of the total tree population analyzed.
Tree Diversity in San Diego, CA
Of the 212,237 trees observed in San Diego, 130 unique tree species were identified, and the effective species number was calculated to be 40.23. This means tree diversity in the city is akin to having 40 species in equal numbers.
The dominant species observed were the Queen Palm (Syagrus romanzoffianum) and Carrot wood (Cupaniopsis anacardioides), each accounting for 10.66% and 6.41% of the total surveyed tree population, respectively.
Other commonly observed trees included various species of Pine and Eucalyptus, and the ten most widely observed trees accounted for 53.59% of the total population in the dataset.
The dominance of certain species and the uneven distribution among species indicate the potential for improved tree diversity in San Diego.
Common Trees in San Francisco, California
San Francisco, California, has a population of around 810,000 and is estimated to have urban tree coverage of about 15%.
The San Francisco Public Works website outlines a goal of planting 50,000 trees by 2035, which would take the urban tree cover from 105,000 to 155,000 trees.
You can request a street tree through Friends of the Urban Forest, an organization committed to revitalizing San Francisco’s urban forest and educating people on the benefits of urban greening.
We analyzed the data on 175,243 trees currently growing in San Francisco, CA, to see which are the most common species found in the city and how diverse the urban forest in San Francisco is.
Here are the results!
Top 10 Most Common Trees Observed in San Francisco, CA
- Sycamore London plane (Platanus acerifolia) – 6.50%
- Brisbane box (Lophostemon confertus) – 5.48%
- New Zealand Christmas Tree (Metrosideros excelsa) – 4.95%
- Victorian box (Pittosporum undulatum) – 3.95%
- Swamp myrtle (Tristaniopsis laurina) – 3.87%
- Cherry plum (Prunus cerasifera) – 3.83%
- Indian laurel fig tree (Ficus microcarpa) – 3.79%
- Southern magnolia (Magnolia grandiflora) – 3.55%
- Hybrid strawberry tree (Arbutus) – 3.18%
- Kwanzan flowering cherry (Prunus serrulata) – 2.31%
* All other species combined comprise 58.59% of the total tree population analyzed.
Tree Diversity in San Francisco, CA
San Francisco boasts 456 different tree species, as observed in this dataset of 175,243 trees. The effective species number was calculated to be 68.95, which means tree diversity in the city is equivalent to having 69 different species of trees in equal numbers.
A significant majority (83.9%) of the trees observed were categorized as introduced (non-native), and only 2.4% were categorized as native. The remaining 13.7% had no information regarding their native status.
The most dominant species observed in San Francisco was the non-native London Plane (Platanus acerifolia), accounting for 6.5% of the total tree population, followed by the Brisbane Box (Lophostemon confertus), comprising 5.48%.
Other dominant species included the New Zealand Christmas Tree (Metrosideros excelsa), Victorian Box (Pittosporum undulatum), and Swamp Myrtle (Tristaniopsis laurina), with the ten most commonly observed trees accounting for less than half of the total tree population (41.41%), a positive indicator of tree diversity in San Francisco.
Overall, San Francisco’s urban forest showcases a diverse array of species with a focus on introduced trees. Increasing the population of native trees may be beneficial in improving the city’s connection to local ecosystems and enhancing the ecological sustainability of urban canopy cover in San Francisco.
Common Trees in San Jose, California
San Jose, California, currently has a population of approximately 970,000, and its urban canopy cover sits at 13.5%, according to the US Forest Service.
Our City Forest has a Cool and Green initiative where residents living in certain areas can apply for a free tree. If you live outside the marked areas, you can utilize the San Jose Tree Rebate Program, where a rebate of up to $100 is available for residents.
We analyzed the data on 264,805 trees currently growing in San Jose, CA, to see which are the most common species found in the city and how diverse San Jose’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in San Jose, CA
- London Plane (Platanus acerifolia) – 9.93%
- Chinese Pistache (Pistacia chinensis) – 9.18%
- Crape Myrtle (Lagerstroemia indica) – 8.17%
- American Sweetgum (Liquidambar styraciflua) – 5.53%
- Callery Pear (Pyrus calleryana) – 3.64%
- Japanese Zelkova (Zelkova serrata) – 2.90%
- Mediterranean Cypress (Cupressus sempervirens) – 2.72%
- Southern Magnolia (Magnolia grandiflora) – 2.67%
- Cherry Plum (Prunus cerasifera) – 2.64%
- Narrow-leaved Ash (Fraxinus angustifolia) – 2.12%
* All other species combined comprise 50.49% of the total tree population analyzed.
Tree Diversity in San Jose, CA
San Jose’s urban forest demonstrates a commendable level of species diversity with a higher presence of non-native trees. There were 478 unique species identified among the 264,805 trees observed, and the effective species number is calculated to be 59.42. This means tree diversity in San Jose is equivalent to having 59 common species in equal numbers.
The top ten trees account for less than 50% of the entire tree population observed in San Jose, and the dominant species (9.93% of the total tree population) is the non-native London Plane (Platanus acerifolia). Other dominant species include the Chinese Pistache (Pistacia chinensis), Crape Myrtle (Lagerstroemia indica), and American Sweetgum (Liquidambar styraciflua).
The diversity of San Jose’s urban canopy contributes to both the city’s visual appeal and the urban landscape’s environmental stability. Increasing the presence of native species may be beneficial in improving connection to the local ecosystem.
Common Trees in Seattle, Washington
Seattle, Washington, has a population of approximately 750,000 and has an urban tree canopy cover of 28.1% as of 2021. The goal is to reach 30% canopy cover by 2037.
The Green Seattle Partnership aims to restore 2,500 acres of forested parklands by 2025, and the Trees for Seattle initiative offers free trees and training to local residents.
We analyzed the data on 164,947 trees currently growing in Seattle, WA, to see which are the most common species found in the city and how diverse Seattle’s urban forest is:
Here are the results!
Top 10 Most Common Trees Observed in Seattle, WA
- Purpleleaf plum variety (Prunus cerasifera) – 5.00%
- Red maple (Acer rubrum) – 3.23%
- Apple/crabapple (Malus) – 2.94%
- Norway maple (Acer platanoides) – 2.82%
- Japanese maple species (Acer palmatum) – 2.77%
- Cherry/plum/laurel (Prunus) – 2.31%
- English midland hawthorn (Crataegus laevigata) – 2.16%
- Kwanzan flowering cherry (Prunus ‘Kwanzan’) – 2.02%
- Sweetgum (Liquidambar styraciflua) – 2.02%
- Blireiana purpleleaf plum (Prunus blireiana) – 1.75%
* All other species combined comprise 72.97% of the total tree population analyzed.
Tree Diversity in Seattle, WA
Of the 164,947 trees observed in Seattle, 73% were categorized as non-native (introduced), and 443 unique tree species were observed. The effective species number was calculated to be an impressive 108.81, the highest of any city included in this analysis. This means that tree diversity in Seattle is equivalent to having 109 species in equal numbers.
The most dominant species observed in Seattle was Purpleleaf Plum (Prunus cerasifera), accounting for 5% of the total tree population. Other commonly observed species included Red Maple (Acer rubrum) and Apple/Crabapple (Malus spp.). The ten most common tree species account for just 27% of the total tree population, another positive indicator of tree diversity in Seattle.
This data demonstrates the rich biodiversity of Seattle’s urban forest, contributing to the city’s ecological sustainability and aesthetic appeal.
Common Trees in Sioux Falls, South Dakota
Sioux Falls, South Dakota, has a population of around 200,000 and the city has various tree-planting initiatives in place aimed at increasing urban canopy cover.
Through workshops, Project Food Forest teaches the public how to grow a food forest and why they are so important. All food grown is available for everyone, and they also work with clients to create private food forests and forest gardens.
There is also a Street Tree Voucher Program through which, if you select a tree from the list and follow the guidelines, homeowners can receive a $50 Voucher.
We analyzed the data on 61,304 trees currently growing in Sioux Falls, SD, to see which are the most common species found in the city and how diverse the urban forest in Sioux Falls is.
Here are the results!
Top 10 Most Common Trees Observed in Sioux Falls, SD
- Green Ash (Fraxinus pennsylvanica) – 34.99%
- Norway Maple (Acer platanoides) – 9.30%
- Freeman Maple (Acer freemanii) – 8.05%
- Silver Maple (Acer saccharinum) – 7.06%
- Littleleaf Linden (Tilia cordata) – 5.05%
- Honeylocust (Gleditsia triacanthos) – 3.62%
- Hackberry (Celtis occidentalis) – 2.61%
- Colorado spruce (Picea pungens) – 2.10%
- Sugar Maple (Acer saccharum) – 2.08%
- Red Maple (Acer rubrum) – 1.61%
* All other species combined comprise 23.52% of the total tree population analyzed.
Tree Diversity in Sioux Falls, SD
Although Sioux Falls has quite a diverse urban forest with 155 unique species observed in this analysis of 61,304 trees, a few species dominate. Green Ash (Fraxinus pennsylvanica) accounts for a huge 34.99% of the tree population, significantly outnumbering other species.
Norway Maple (Acer platanoides), Freeman Maple (Acer freemanii), and Silver Maple (Acer saccharinum) are among the other most common tree species observed in Sioux Falls.
Out of the 155 tree species observed in Sioux Falls, we calculated the effective number of species to be 16.63. This means that the diversity is akin to having just 17 species in equal numbers. Inadequate species diversity in Sioux Falls is further evidenced by the fact that the ten most commonly observed trees account for 76.48% of the total tree population observed.
This uneven distribution, coupled with the dominance of a few species species, indicates that tree diversity in Sioux Falls can be improved upon.
Common Trees in St. Louis, Missouri
St. Louis, Missouri, has a population of approximately 285,000 and has some excellent tree-planting initiatives.
Residents can request a street tree at no charge, or if you are interested in planting on public, personal, or not-for-profit property, trees can be obtained either free or at a reduced cost through Forest ReLeaf of Missouri.
We analyzed the data on 83,535 trees growing in St. Louis, MO, to see which are the most common species in the city and how diverse the urban forest is.
Top 10 Most Common Trees Observed in St. Louis, MO
- Red maple (Acer rubrum) – 10.26%
- Green ash (Fraxinus pennsylvanica) – 9.29%
- Callery pear (Pyrus calleryana) – 8.61%
- Pin oak (Quercus palustris) – 7.78%
- White ash (Fraxinus americana) – 5.46%
- Sugar maple (Acer saccharum) – 4.99%
- Littleleaf linden (Tilia cordata) – 4.34%
- Silver maple (Acer saccharinum) – 3.73%
- Eastern redbud (Cercis canadensis) – 3.40%
- Thornless honeylocust (Gleditsia triacanthos) – 3.37%
* All other species combined comprise 38.77% of the total tree population analyzed.
Tree Diversity in St. Louis, MO
The dataset for St. Louis included observations on 83,535 individual trees, and out of those, 228 unique species were identified. The effective species number is 33.02, meaning tree diversity in St. Louis is akin to having 36 different tree species in equal numbers.
The urban forest in St. Louis is dominated by Red Maple (Acer rubrum), the most prevalent species observed, accounting for 10.26% of the total tree population.
Other dominant species in St. Louis include Green Ash (Fraxinus pennsylvanica), Callery Pear (Pyrus calleryana), and Pin Oak (Quercus palustris), each comprising 9.29%, 8.61% and 7.78% of the total tree population, respectively.
A substantial portion of the trees were categorized as native (over 63%), with 30% classified as introduced (non-native). The remaining trees (7%) were not organized into either category.
This data indicates that while the urban forest in St. Louis is richly diverse, the dominance of certain species does mean further diversification may be needed.
Common Trees in Stockton, California
Stockton, California, has a population of approximately 320,000 and has been recognized as a ‘Tree City USA’ by the Arbor Day Foundation for its commitment to urban forestry.
Oak Grove Regional Park is a notable green space in Stockton, home to a variety of native trees and majestic oaks.
Thanks to the city’s Urban Forest Program in conjunction with Puentes, homeowners, and businesses can apply to receive a free native Valley Oak tree to plant in their own front yard!
We analyzed the data on 97,707 trees growing in Stockton, CA, to see which are the most common species in the city and how diverse Stockton’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Stockton, CA
- Chinese pistache (Pistacia chinensis) – 11.66%
- London plane tree (Platanus acerifolia) – 7.73%
- Crape myrtle (Lagerstroemia indica) – 7.53%
- Chinese hackberry (Celtis sinensis) – 7.35%
- Ornamental pear (Pyrus calleryana) – 5.42%
- Modesto ash (Fraxinus velutina) – 4.54%
- American sweetgum (Liquidambar styraciflua) – 4.21%
- Southern magnolia (Magnolia grandiflora) – 3.85%
- Sawleaf zelkova (Zelkova serrata) – 3.46%
- Coast redwood (Sequoia sempervirens) – 3.00%
* All other species combined comprise 41.26% of the total tree population analyzed.
Tree Diversity in Stockton, CA
Stockton has a reasonably diverse urban forest with 280 unique tree species observed in this analysis. We calculated the effective species number to be 41.76, which means tree diversity in Stockton is equivalent to having 42 tree species in equal numbers.
Of the 97,707 trees observed, 77,289 (79%) were categorized as introduced (non-native). The Chinese Pistache (Pistacia chinensis) and London Plane (Platanus acerifolia) were the most dominant among the introduced tree species.
Other prevalent species included the Crape myrtle (Lagerstroemia indica), Chinese Hackberry (Celtis sinensis), and Ornamental Pear (Pyrus calleryana).
Overall, the urban forest in Stockton showcases a wide variety of different tree species with an emphasis on non-native species. The dominance of certain species combined with the uneven distribution among species suggests that further diversification would be beneficial, particularly of native species, to support the local ecosystems.
Common Trees in Tampa, Florida
Tampa, Florida, has a population of approximately 400,000, and Mayor Jane Castor has announced a goal of planting 30,000 new trees by 2030.
Also, the Tree-mendous Tampa Free Tree Program can be utilized by residents to apply for up to 2 free trees per year to be planted in the street outside their property.
TREE Inc. has planted over 31,000 trees in Tampa since 1983 and is educating the public about the benefits of planting and preserving trees through its various projects and programs.
We analyzed the data on 25,068 trees growing in Tampa, FL, to see which are the most common species in the city and how diverse Tampa’s urban forest is.
Top 10 Most Common Trees Observed in Tampa, FL
- Live oak (Quercus virginiana) – 22.67%
- Sand live oak (Quercus geminata) – 15.31%
- Crapemyrtle (Lagerstroemia indica) – 11.60%
- Cabbage palm (Sabal palmetto) – 5.61%
- Slash pine (Pinus elliottii) – 5.18%
- Laurel oak (Quercus laurifolia) – 5.11%
- Washington fan palm (Washingtonia robusta) – 4.22%
- Carolina cherry laurel (Prunus caroliniana) – 3.42%
- Bottlebrush (Callistemon viminalis) – 2.22%
- Bald cypress (Taxodium distichum) – 1.99%
* All other species combined comprise 22.68% of the total tree population analyzed.
Tree Diversity in Tampa, FL
The urban canopy in Tampa comprises a mix of tree species, with native species more prevalent than introduced (non-native). Of the 25,068 trees observed, 184 unique species were identified, and an effective species number of 20.16 was calculated. This means that tree diversity in Tampa is akin to having 20 different tree species in equal numbers.
Among the most prevalent species were the native Sand Live Oak (Quercus geminata), Cabbage Palm (Sabal palmetto), and Slash Pine (Pinus elliottii). However, the overwhelmingly dominant species is the native Live Oak (Quercus virginiana), which accounts for a massive 22.67% of the total population of trees observed.
The dataset showcases Tampa’s urban forest as primarily comprised of a charming mix of palms and oaks. However, the dominance of a single species combined with the uneven distribution among species indicates the potential for improvement in overall species diversity in Tampa.
Common Trees in Washington, District of Columbia
As the capital of the United States, Washington, D.C., has significant historical and political importance. Its population is approximately 700,000, and the city is known for its many landmarks.
Washington, D.C., is often called the “City of Trees” as it has a vast and extensive tree canopy that covers roughly 37% of its land area.
There are fantastic tree-planting initiatives for residents that include planting shade trees for residents free. These initiatives are aimed at improving health, privacy, habitat, and much more.
We analyzed the data on 168,705 trees growing in the city to determine which species are found most commonly in Washington, DC, and how diverse the city’s urban forest is.
Top 10 Most Common Trees Observed in Washington, D.C
- Red maple (Acer rubrum) – 7.43%
- Willow oak (Quercus phellos) – 5.93%
- Pin oak (Quercus palustris) – 5.23%
- Red oak (Quercus rubra) – 3.48%
- American elm (Ulmus americana) – 3.44%
- Japanese zelkova (Zelkova serrata) – 3.23%
- Sugar maple (Acer saccharum) – 3.19%
- London plane tree (Platanus acerifolia) – 2.93%
- Crape myrtle (Lagerstroemia indica) – 2.58%
- Chinese elm (Ulmus parvifolia) – 2.22%
* All other species combined comprise 60.34% of the total tree population analyzed.
Tree Diversity in Washington, D.C
The Washington, D.C. dataset included observations on 168,705 individual trees, and among those, 154 unique species were identified. The effective species number was calculated to be an impressive 56.78, which means that tree diversity in the city is equivalent to having 57 species of trees in equal numbers.
The city’s urban forest is characterized by a mix of both native and introduced tree species, with a strong emphasis on native trees. The most dominant species observed was the native Red Maple (Acer rubrum), accounting for 7.43% of the total tree population in the dataset.
Other common trees in Washington D.C. included several species of oak: Willow Oak (Quercus phellos), Pin Oak (Quercus palustris), and Red Oak (Quercus rubra).
The ten most dominant trees accounted for less than 40% of the total tree population, another positive indicator of species diversity in Washington’s urban forest.
Common Trees in Watertown, Wisconsin
Watertown, Wisconsin, has a population of approximately 23,000.
While the city doesn’t have any local tree-planting initiatives that we could find, Governor Tony Evers does have a pledge to plant 75 million trees in Wisconsin by 2030.
We analyzed the data on 6,145 trees growing in Watertown, WI, to see which are the most common species in the city and how diverse Watertown’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Watertown, WI
- Norway maple (Acer platanoides) – 15.88%
- Littleleaf linden (Tilia cordata) – 6.53%
- Callery pear (Pyrus calleryana) – 6.46%
- Honeylocust (Gleditsia triacanthos) – 6.27%
- Crabapple (Malus tschonoskii) – 5.76%
- White ash (Fraxinus americana) – 5.48%
- Japanese tree lilac (Syringa reticulata) – 4.64%
- Green ash (Fraxinus pennsylvanica) – 4.21%
- Silver maple (Acer saccharinum) – 3.97%
- Freeman maple (Acer freemanii) – 3.32%
* All other species combined comprise 37.48% of the total tree population analyzed.
Tree Diversity in Watertown, WI
In Watertown, 6,145 trees were observed, and 87 unique species were identified. The effective species number was calculated to be 30.13, which means tree diversity in Watertown is akin to having 30 different species of trees in equal numbers.
The most dominant species observed was the Norway Maple (Acer platanoides), comprising 15.88% of the total tree population and significantly outnumbering other species.
Other prevalent species included the Littleleaf linden (Tilia cordata), Callery pear (Pyrus calleryana), and Honeylocust (Gleditsia triacanthos).
Overall, Watertown’s urban forest showcases a reasonably diverse mixture of both native and introduced (non-native) trees. However, the dominance of the Norway Maple, combined with the uneven distribution among other species, does indicate a potential need for further tree diversification in Watertown.
Common Trees in Worcester, Massachusetts
With a population of approximately 185,000, Worcester, Massachusetts, is the 2nd largest city in the state.
Worcester boasts an impressive statistic of having roughly 37% tree cover across the city area, which is a testament to the stewards of this city.
We crunched the numbers on 15,477 trees currently growing in the city to determine which species are found most commonly in Worcester, MA, and how diverse the city’s urban forest is.
Here are the results!
Top 10 Most Common Trees Observed in Worcester, MA
- Norway Maple (Acer platanoides): 60.50%
- Sugar Maple (Acer saccharum): 8.70%
- Red Maple (Acer rubrum): 6.65%
- Silver Maple (Acer saccharinum): 2.21%
- Littleleaf Linden (Tilia cordata): 2.16%
- Northern Red Oak (Quercus rubra): 2.11%
- Callery Pear (Pyrus calleryana): 1.74%
- Pin Oak (Quercus palustris): 1.71%
- White Ash (Fraxinus americana): 1.45%
- Honey Locust (Gleditsia triacanthos): 1.18%
* All other species combined comprise 11.58% of the total tree population analyzed.
Tree Diversity in Worcester, MA
Worcester has a relatively modest variety of tree species, with a total of 95 unique species identified among the 15,477 trees observed in this analysis. While the number of unique species creates a sense of diversity, the effective species number of 6.43 paints a more nuanced picture. This number means tree diversity in Worcester is akin to having just 6 species of trees in equal numbers.
Further analysis of the dataset indicates the overwhelming dominance of a single tree species, with the Norway Maple (Acer platanoides) alone accounting for 60.5% of the total tree population in the dataset.
Other dominant species included the Sugar Maple (Acer saccharum) and Red Maple (Acer rubrum), comprising 8.7% and 6.65% of the total population.
With the ten most dominant trees accounting for 88.42% of the total tree population observed, Worcester’s lack of diversity is further emphasized.
Why Does Tree Diversity Matter?
Beyond the obvious aesthetic appeal of a diverse urban forest, maintaining tree diversity is essential for the health and resilience of the tree population.
Ecological Health and Resilience
Many pests and diseases that impact trees are species-specific, so when a single species of trees comprises a large percentage of the total tree population in an urban area, the vulnerability of the urban canopy is increased.
For example, once dubbed the ‘City of Elms,’ Minneapolis, Minnesota, lost approximately 100,000 elm trees to Dutch Elm Disease in the 1970s. This cost the city roughly $60 million over the course of a decade, with funds directed to tree and stump removal, insect and disease control, and inspection and replanting.4
Other examples of tree populations being devastated by pests or disease include the loss of tens of millions of trees in Michigan in the early 2000s to Emerald Ash Borer (EAB) and Sudden Oak Death (SOD), first detected in the San Francisco Bay area and responsible for the deaths of millions of tanoak, coast live oak, California black oak, and other native species.
These are just a few of many examples where tree populations have been devastated by pests or disease, and they serve to highlight the need for diversification of tree species in urban forests.
With a diverse urban canopy, the risk of losing a significant portion to any one pest or disease is significantly decreased. Additionally, disease and pest pressure are reduced compared to when a monoculture or over-representation of a single tree species exists.
Climatic Tolerance
Pests and diseases are not the only challenges urban forests are faced with. They also need to contend with climate variability.
Different tree species have varied tolerance to heat, drought, excessive rainfall, strong winds, pollution, and other environmental pressures. By planting a diverse range of species, an urban forest is better equipped to handle these pressures since the conditions that some trees might struggle in can be the very same conditions in which others will thrive.
For example, in Denver, Colorado, approximately 15% of the trees that make up the city’s urban forest are ash species. These are already under threat from Emerald Ash Borer (EAB), but they also face challenges from periodic drought that affects the region. Drought-stressed trees are more vulnerable to attack from pests, and the lack of species diversity compounds this vulnerability.
Economic and Social Value
Diverse urban forests also have many economic benefits, from increased property value due to enhanced aesthetics and economic uses such as food or timber production.
Due to the reduced impact of a potential disease or pest outbreak, maintenance costs are reduced, and large-scale replacement costs are avoided.
A diverse urban forest also serves to improve air quality and aid in city noise reduction and stormwater management. For example, an urban forest comprising mostly deciduous species will have minimal impact on air quality or carbon sequestration during their dormant period.
By providing different habits and food sources, a diverse urban forest can also support a broader range of wildlife, including birds, mammals, insects, and microorganisms.
Sustainability
Diverse tree species are vital to the overall health and sustainability of urban forests. As urban areas continue to expand, ensuring diversity is crucial, not just for the integrity of urban forests but also for the well-being of neighboring rural forests.
Effective Number of Species
The Shannon Diversity Index formula was used to calculate diversity, and the effective number of species (ENS) was derived from this index for each city. The resulting number considers both the richness and evenness of species distribution, providing valuable insights into biodiversity.
Species Richness
Species richness is determined by the number of unique species identified within each dataset. High species richness indicates a diverse and complex ecosystem, providing greater resilience to environmental challenges, pests, and diseases. It also contributes to aesthetic appeal and habitat variety for urban wildlife.
Species Evenness
Species evenness measures how evenly individual trees are distributed among different species within the population of observed trees. Species evenness considers the number of species present and the number of individual trees within each species. This provides insight into the balance and stability of the ecosystem, helping to prevent the overdominance of certain species.
Effective Number of Species Calculation
The Shannon Diversity Index (H) was calculated using the following formula:
H = – ∑ (pi × ln (pi))
Where:
- H is the Shannon Diversity Index
- pi is the proportion of individuals that belong to species i
- ln is the natural logarithm
The number of unique species was based on scientific names provided in the dataset, and the total tree population for each city was used in the calculation.
Understanding the Effective Number of Species
The effective number of species (ENS), derived from the Shannon Diversity Index, is a useful measurement combining the richness and evenness of a tree population. Unlike the species richness count, which only indicates how many different species of trees are present, the ENS provides an indication of how those species are distributed among individual trees.
A city with a low ENS might have an urban forest comprising a limited variety of species, one or two dominating species, or both. This can lead to vulnerabilities such as increased susceptibility to diseases or pests that target the dominant species.
On the other hand, a city with a high ENS is likely to have a diverse urban forest comprising a wide variety of species, with no overly dominant species. This creates ecological stability and provides a buffer against diseases, pests, and environmental changes that may severely affect one particular species.
Examining the ENS provides insights into the health and resilience of urban tree populations and helps city planners, conservationists, and ecologists to better plan for diverse and sustainable urban forests.
Data Source
McCoy, Dakota et al. (2022), A dataset of 5 million city trees from 63 US cities: species, location, nativity status, health, and more., Dryad, dataset, https://doi.org/10.5061/dryad.2jm63xsrf
License: CC0 1.0 Universal Public Domain Dedication
Cleaning Process
Each of the original datasets was ‘cleaned’ to provide useful insights into urban canopy cover in each city. The following entries were removed from the dataset; ‘vacant,’ ‘NA,’ ‘dead,’ and ‘stump,’ in addition to any other anomalous entries that did not provide useful information about the tree species within each city.
Some datasets were missing the common names of the trees observed; for these, the most widely used common name was included in the analysis. Since trees often have several different common names, often location specific, the name chosen for the analysis may not match the common name the tree is known by in each city.
Some of the cities in the original dataset were also removed from this analysis as the number of trees observed within the city was deemed too low to provide useful insights into the city’s urban canopy cover. For example, the Phoenix, AZ dataset only included observations on 210 trees. Other cities excluded from the analysis included Jersey City, Miami, and Santa Rosa.
The Milwaukee dataset included observations on trees within the city of Milwaukee and in other smaller cities, towns, and villages within and around the county. These were separated into their own datasets, and only the cities with a significant number of tree observations were included; Milwaukee (city), New Berlin, and Watertown.
The following cities, towns, and villages were excluded; Wauwatosa, Glendale, West Allis, Brown Deer, Hales Corners, South Milwaukee, Cudahy, Greenfield, Franklin, Greendale, Oak Creek, Fox Point, West Milwaukee, Shorewood, Whitefish Bay, Cedarburg, West Bend, Muskego, Wind Lake.
The original Honolulu dataset included observations on trees within the city of Honolulu and other towns and census-designated places within Honolulu County. For the purpose of this analysis, these were separated into their own datasets, and only the locations with a significant number of tree observations were included; Honolulu (city), Kaneohe, and Kailua.
The following locations were excluded from the analysis; Waipahu, Ahuimanu, Heeia, and Aiea, as each had fewer than 43 tree observations.
Disclaimer
It should be noted that this analysis is limited by the information contained in the original dataset. The sample size and collection process for each city varied. While the resulting dataset may not accurately represent urban canopy cover in every case, some useful insights about canopy cover in the cities can be obtained.
While all attempts have been made to provide accurate information, we are not responsible for any inaccuracies that occurred during the data collection process. We have done our best to provide insightful and accurate analyses based on the information in the original dataset. If you notice any mistakes in our work, please get in touch with us, and we will do our best to correct any inaccuracies.
Conclusion
Urban areas are expanding in the US, but tree cover in urban areas has declined in recent years. Cities are proactively growing their urban canopy, with local tree-planting initiatives active in most of the 63 cities included in this analysis.
Over 5 million trees were included in the dataset, and the London planetree (Platanus acerifolia) was observed in the highest numbers. Crape myrtle (Lagerstroemia indica), Norway maple (Acer platanoides), Honeylocust (Gleditsia triacanthos), and Callery pear (Pyrus calleryana) were the other dominant tree species identified.
The median number of unique species comprising each urban forest was 153, and the median effective number of species was 34.53. This means that species diversity in most cities is akin to having 35 different species in equal numbers.
Seattle, WA, had the highest diversity score with an effective number of species (ENS) count of 108.81. By comparison, Worcester, MA, has the lowest diversity score with an ENS of 6.43.
Species diversity is vital for healthy, resilient urban forests, which are critical to human health and well-being.
Data Sources
1 David J Nowak and Eric J Greenfield (2018), US Urban Forest Statistics, Values, and Projections, Journal of Forestry, Volume 116, Issue 2, March 2018, Pages 164–177, https://doi.org/10.1093/jofore/fvx004
2 David J. Nowak and Eric J. Greenfield (2018), Declining urban and community tree cover in the United States, Urban Forestry & Urban Greening, Volume 32, May 2018, Pages 32-55, https://doi.org/10.1016/j.ufug.2018.03.006
3 McCoy, Dakota et al. (2022), A dataset of 5 million city trees from 63 US cities: species, location, nativity status, health, and more., Dryad, dataset, https://doi.org/10.5061/dryad.2jm63xsrf
4 French, D.W. (n.d.). History of Dutch Elm Disease in Minnesota. University of Minnesota Digital Conservancy. https://conservancy.umn.edu/
