Poplar trees are incredibly fast-growing, often very tall, deciduous trees with lovely yellow to golden fall colors.
Poplars all belong to the Salicaceae or Willow Family of flowering trees and shrubs.
Poplars are all in the Populus genus, with 35 currently accepted species worldwide. This genus also includes trees that go by the common names of aspen and cottonwood.
Based on fossil evidence, the Populus genus evolved at least 59 million years ago, not long after the dinosaurs went extinct and worldwide diversification was occurring in all living organisms.
Poplar trees are native throughout most of the Northern Hemisphere. The southernmost species is the Tana River Poplar (Populus ilicifolia) of Kenya and Tanzania from 1°N to 3°S.
Tulip Trees, sometimes called Tulip Poplars, are not poplars but part of the Magnoliaceae family.
Poplars are all deciduous trees that lose their leaves in the fall. They often turn pleasing shades of yellow, gold, or sometimes orange or red, providing lovely fall color to the landscape. The leaves re-grow from buds the following spring.
The different species of poplars have different characteristic shapes to their leaves. Many are also heterophyllous or dimorphic, meaning that they have two different types of leaves on the tree simultaneously.
Poplars have normal shoots (preformed shoots) that develop from winter buds and contain the primordia of all the leaves that will grow during that season. They also have new growth, which contains leaves not preformed in a bud (neoformed). The leaves of neoformed shoots often appear quite different than those from normal shoots.
For the purpose of identifying poplar trees, just knowing that sometimes not all the leaves will look the same and understanding the range of variation is usually sufficient.
Poplar leaves come in various sizes and shapes. They may be egg-shaped (ovate), diamond-shaped (rhombic), triangular (deltoid), somewhat rounded (suborbicular), elliptical, heart-shaped (cordate), or lance-shaped (lanceolate – sometimes described as narrowly ovate but these ones have a length to width ratio of 3:1 or greater).
Leaf shape is an important tool in identifying the different poplar trees.
Leaves also have characteristic shapes to their bases which can help identify the different types of poplar trees.
Their bases may be heart-shaped (cordate), truncate (appears as though cut off abruptly), wedge-shaped (cuneate), rounded, obtuse (wide-angled), or sometimes earlobe-shaped (auriculate, which is like cordate but with the bottom lobes typically being narrower and bending in towards the stem a little).
The shape of the leaf tip or apex is also used to help identify the different types of poplar trees. There is much less variability in poplar leaf tips, but they can be acute (angled at less than 90°), obtuse (wide-angled, greater than 90°), or sometimes long-pointed (acuminate), where they narrow to a very fine point where the tip is an angle of less than 30°.
Poplar leaves are also described by their leaf margins which can be entire (smooth, without any teeth or other features), or they can have rounded teeth (crenate) or serrated teeth (sharp, angular). Many poplars have teeth that are crenate-serrate, which is simply intermediate between rounded and angular.
Their margins may also be lobed, having distinct protrusions which are sometimes very obvious or sometimes can be hard to distinguish from large teeth. Finally, their margins may also be ciliate, which is a layer of fine hairs running along the margin’s edge.
Leaf stalks or petioles on poplars can be either rounded or flattened, or sometimes they are only slightly flattened. Leaf stalks are often about as long as the length of the leaf, but some are much shorter, which can be used as a good identification tool.
Some poplar leaf stalks have widened bases (like a pulvinus). Some are hairy (pilose or tomentose), while others are hairless. Others have unique characteristic colors, and some have channels on them. All of these factors can help identify the different species of poplar.
Many poplar trees have hairs on their leaves, young and sometimes mature twigs, winter buds, and even the rachis of the catkins. The presence and type of hairs found can be used to help identify the different types of poplars.
Many poplars with hair have tomentose hair, which is a kind of matted woolly-looking hair. Sometimes the hairs can be pilose, which are soft, straight, and long hairs. Or they can be downy (pubescent), which is soft like pilose, but the hairs are short. Finally, some hairs are described as appressed when they are pressed against the leaf, twig, or petiole, all facing the same direction.
Poplars, being deciduous trees, develop buds on their branches which contain the primordia of the leaves that will develop the following spring. These buds come in various shapes but are usually egg-shaped, with short or long-pointed tips. They have characteristic colors, may be smooth and shiny or hairy, or have basal scales that might be hairy, and some release often fragrant resin that may be red or yellow.
These factors are all useful in identifying poplars, especially in winter after they have lost their leaves. In winter, you can examine the winter buds, along with the bark and twig characteristics and the overall size and shape of the tree, and sometimes still identify it even without any leaves or catkins.
Poplars are almost always dioecious trees with separate male and female trees. And being angiosperms, they have separate male and female flowers on those trees. In very rare instances, poplars can be monoecious, with separate male and female flowers on the same tree.
Poplars produce their flowers in elongated spikes known as catkins. Unlike many other catkin-producing plants that produce only male catkins, while female flowers tend to be solitary, the entire Populus genus produces both male and female catkins.
Catkins typically contain numerous tiny flowers, usually more than ten and sometimes 100 or more, that are all attached to a central stalk known as a rachis.
The flowers are very tiny and, in all Populus species, they are very reduced compared to most angiosperms because they lack petals or sepals, vestigial parts, staminodes, or nectaries of any kind.
In fact, every single tiny flower consists only of a characteristic number of stamens (male flowers) or stigmas in their pistil (female flowers), along with a usually brownish subtending bract. Bracts are not considered petals or sepals because they are derived from leaf tissue rather than floral parts.
Stamens are the male reproductive structures of a plant. They are usually made of a filament (like a stalk) topped with an anther which is the reproductive structure that produces and releases pollen.
In poplars, there are typically numerous stamens per flower (often more than 30) that are difficult to count without a dissection kit and a magnifying glass. However, they sometimes have a characteristic color that can be used to help identify certain species.
A pistil is the entire reproductive structure of a female flower. It includes an ovary containing ovules (think of these as unfertilized seeds) plus a characteristic number of stigmas, often held above the ovary on a style (a stalk).
The stigmas are the receptive structures that receive the pollen and direct it into the ovary, where it fertilizes the ovules to create seeds. The ovary is usually situated immediately beneath the stigma. Stigmas are often variously colored, shaped, and lobed, which can be used to aid in identification.
Poplars, being flowering plants of the angiosperm phylum, produce fruits formed from their ovaries. All poplars produce the same type of dry dehiscent fruit known as a capsule.
Capsules look like large seeds that hang from a usually elongated catkin after the flowers are long gone. Capsules are green when immature and typically turn brown when they mature, dry, and split open (dehiscence) into a characteristic number of valves to release their numerous seeds. Most Populus species have two valves, so when the valves are visible, and they have three or more, this can be used to help identify the different types of poplars.
The interesting thing about poplars is that in some species, the seeds seldom germinate. Instead, in those species, they spread clonally by their roots producing clonal plants. Those clonal plants then spread through their roots, creating more clonal plants, and so on, until they produce almost pure stands of the same genetically identical trees. This is one way that poplars have sometimes become very invasive.
Tree habit is the overall shape of a tree as viewed from a distance. Poplars tend to have columnar, conical, or open rounded crowns. Trees often begin their lives with pyramidal or conical crowns that spread and become more open, rounded, or irregular with age.
Some poplars’ trunks are forked, producing two or more main stems. Sometimes their trunks fork so repeatedly that they no longer have a main trunk. This is a common feature in trees that have spreading crowns.
How the branches are arranged on a tree can also sometimes be used to help identify the different types of poplars. However, in poplars, there is not as much variability as seen in some groups of trees.
They tend to have either ascending or spreading branches. Sometimes the spreading branches can be thought of as ascending and descending, but when we see both on the same tree, we call it spreading because the branches are spreading widely.
Sometimes in poplars, especially in columnar cultivars, their branches are so strongly ascending they could almost be called vertical or erect.
One final feature to help identify the different types of poplar trees is their bark. Poplar bark tends to be thin, light, and smooth when young but then typically gets thick and often deeply grooved (furrowed) as it matures.
The color of the bark and if it develops these grooves can sometimes help identify the different types of poplars. It can easily differentiate a poplar from an aspen which lacks the thick bark with vertical grooves.
Since poplar, aspen, and cottonwood are all from the same Populus genus, they naturally share most of their general morphological characteristics. This can make them difficult for an untrained eye to tell them apart. But there are some general but important differences between the groups that will help you quickly differentiate them.
Poplars are by far the most variable group. They are generally tall trees with variable crowns. They have variable leaf sizes and shapes that are egg-shaped, triangular, diamond-shaped, or somewhat lance-shaped, with margins that are not typically toothed but can be.
Some poplars have the flattened petioles that aspen has, some are slightly flattened, and others are rounded like cottonwood. Some poplars produce the same cottony seeds as cottonwood, while others do not. Poplar bark tends to get thick and grooved when it matures, similar to cottonwood.
Cottonwoods are often quite massive trees with more triangular or heart-shaped leaves that are usually shallowly toothed or serrated and have rounded leaf stalks that are never flattened.
All cottonwoods produce the characteristic cottony seeds that they get their name from. Finally, cottonwood tends to have very thick and deeply grooved bark as it matures, similar to most poplars, but usually thicker and more deeply grooved.
Cottonwoods and poplars share most characteristics, and their common names often reflect this since many species are called both cottonwood and poplar.
Aspens tend to be smaller trees with relatively small and more rounded leaves that are typically rounded-toothed or serrated-toothed and always have flattened leaf stalks (petioles) which allows them to flutter characteristically in the wind.
They sometimes produce cottony seeds similar to cottonwood, but these seldom germinate, and they mostly regenerate through the clonal spreading of root clones.
Aspen bark tends to remain thin and more or less smooth as it matures, only developing shallow grooves near the trunk base on mature and large trees, very unlike poplars and cottonwoods. Their wood is also much lighter in color, almost white, compared to poplars and cottonwoods.
1. Necklace Poplar (Populus deltoides)
Necklace Poplars are tall trees with a wide spreading crown with thick light to gray-brown deeply grooved bark, sometimes v-grooved, on a stout trunk (up to 9’ 2”).
Buds are greenish-yellow, smooth or stiff-hairy, and have fragrant yellow resin.
It sometimes has dimorphic leaves on slightly flattened stalks about equal to the leaf length. Leaves are broadly triangular, 1 – 5” long, slightly longer than wide, with a truncate, heart-shaped, or broadly wedge-shaped base and a short or long-pointed tip.
Leaves are grayish-green to bright green and hairless, with noticeably toothed margins that may be rounded to serrated.
Catkins are short-stalked, loosely 3 – 55-flowered, and 2 – 9.5” long. Male flowers have numerous stamens, and female flowers have 2 – 4 spreading plate-like stigmas.
Capsules are smooth, egg-shaped, 4(3)-valved, and 0.16 – 0.5” long.
It has been introduced worldwide and is considered invasive in Belgium.
Other Common Names: Eastern Cottonwood, Alamo, Carolina Poplar, Common Cottonwood, Eastern Poplar, Plains Cottonwood, Plains Poplar, Southern Poplar, Rio Grande Cottonwood
Identifying Features: Necklace Poplar has a very thick trunk with thick, deeply grooved gray bark, broadly triangular 1 – 5” leaves with pointed tips and rounded-toothed to serrated margins, buds with fragrant yellow resin, loosely flowered 2 – 9.5” long catkins with numerous stamens in the male flowers, and 4(3)-valved capsules. It is most often mistaken for the Fremont Cottonwood (Populus fremontii), but that one often has V-grooved bark and usually more heart-shaped leaves with coarsely rounded-toothed margins and rounded 2-4-valved capsules.
Native Area: Most of eastern North America from Alberta east to Quebec in Canada, Montana south to New Mexico, and all east of that in the USA, plus some disjunct populations in northeastern Mexico
USDA Growing Zones: 2 – 9
Average Size at Maturity: 65 to 100 ft (to 120 ft) tall, 35 – 60 ft spread
Some Cultivars Available:
2. Black Poplar (Populus nigra)
Black Poplars are medium to tall trees with rounded, spreading crowns and dull gray bark that becomes dark and grooved with age.
Twigs are yellowish, rounded, and hairless.
Buds are russet-colored, egg-shaped, and very resinous.
Leaves are diamond-shaped to somewhat egg-shaped or triangular, 2 – 4” long, sometimes broader than long, greenish on the lower surface, with a variously wedge-shaped or rarely truncated base, a long-pointed tip, and finely toothed margins that are rounded-serrated and ciliate. The noticeably flattened leaf stock is as long as or longer than the leaf.
Male catkins are 2 – 2.4” long with numerous purplish-red anthers per flower.
Female catkins are 2 – 4” long with two stigmas per flower.
Capsules are stalked, egg-shaped, two-valved, and 0.2 – 0.28”.
Other Common Names: Black Cottonwood, Lombardy Poplar (the cultivar, but also used for the type species)
Identifying Features: Black Poplar has dark gray and deeply grooved bark when it matures, diamond-shaped to triangular 2 – 4” long leaves with finely toothed and ciliate margins and a flattened leaf stalk, yellowish and rounded hairless twigs, russet egg-shaped very sticky buds, 2 – 2.4” male catkins with numerous purplish anthers, and two-valved capsules. It is mostly mistaken for the Necklace Poplar, but that one usually has triangular leaves with more rounded-toothed to serrated margins, buds with fragrant yellow resin, and 4(3)-valved capsules.
Native Area: Europe, northwestern Africa, western Asia
USDA Growing Zones: 2 (with protection) – 9
Average Size at Maturity: 40 – 50 ft (to 130 ft) tall, 15 – 20 ft spread
Some Cultivars Available:
- Theves Poplar Populus nigra ‘Afghanica’ is an upright, narrowly columnar tree with leaves that are dark green above and silvery below that turn a mellow gold in the fall, they also have white bark and produce no pollen – Image via Nature Hills
- Lombardy Poplar Populus nigra ‘italica’ is a medium-sized version with a much more compact columnar habit. It is considered highly invasive throughout North America and worldwide – Image via Fast-Growing-Trees
*Combined by Lyrae Willis for Tree Vitalize
3. Canadian Poplar (Populus x canadensis)
Canadian Poplar is a natural hybrid of the Black Poplar from Europe and the North American Necklace Poplar, though its name is unchecked and requires verification.
Being a hybrid, its characteristics are intermediate between the two parent strains.
It has a broadly columnar crown and smooth grayish bark that becomes grooved when mature.
Its leaves are triangular but wider and larger than in Necklace Poplar, with a straight base that is often truncated and margins that are rounded-toothed or serrated. It has a very long leaf stalk that is visibly flattened.
It has been introduced in eastern Canada and sporadically throughout the entire USA, where USDA plants database considers it native despite one parent being an invasive introduced species.
It is listed as introduced in 22 countries worldwide and has become problematic in some of those.
Other Common Names: Carolina Poplar
Identifying Features: The Canadian Poplar is a hybrid of the Black Poplar and the Necklace Poplar, and its traits are mostly intermediate between its parent strains. Its leaves are triangular rather than usually diamond-shaped seen in Black Poplar, but they are larger and wider than those seen in Necklace Poplar. It differs from both its parents in having a broadly columnar crown rather than one that is rounded or spreading.
Native Area: They grow naturally anywhere Black Poplar and Necklace Poplar overlap in ranges
USDA Growing Zones: 4 – 9
Average Size at Maturity: 70 – 135 ft tall, 40 – 80 ft spread
4. Balsam Poplar (Populus balsamifera)
Balsam Poplar is a tall, often clonally spreading northern wetland tree with a narrowly pyramidal crown becoming broadly rounded with spreading branches and reddish-gray plated, then deeply grooved bark.
Twigs are reddish-brown, becoming grayish, rounded, and hairless to hairy.
Winter buds are long and shiny reddish and release very fragrant red resin.
The leaf stalks are slightly flattened and ⅓ – ½ the leaf length.
Leaves are variously egg-shaped, 1 – 6”, ½ – ⅔ as wide as long, with a rounded, obtuse, or almost heart-shaped base and an obtuse to acute tip. Lower surfaces have prominent veins and noticeable reddish-orange resin stains. Upper surfaces are smooth dark green, and margins are almost entire to finely crenate-serrate.
Catkins are short-stalked, somewhat loosely 35 – 80-flowered, and 3 – 6” long.
Male flowers have numerous stamens. Female flowers have 2 – 4 plate-like reflexed stigmas.
Capsules are two-valved, egg-shaped, and 0.1 – 0.3”.
Other Common Names: Balm-of-Gilead, Bam, Ban Tree, Tacamahac Poplar, Cottonwood, Heartleaf Balsam Poplar, Eastern Balsam-poplar, Hackmatack
Identifying Features: Balsam Poplar is relatively easy to identify with its reddish-gray plated, then deeply grooved bark, long, shiny, reddish winter buds with very fragrant red resin, slightly flattened leaf stalks ⅓ – ½ the leaf length, and variously egg-shaped leaves with prominent veins and red resin stains on the lower surfaces. It is often mistaken for Quaking Aspen (Populus tremuloides), but that one usually has white bark that always remains smooth and has only slightly resinous buds. It is also mistaken for Western Balsam Poplar, which has leaf stalks with a swollen base, leaves that lack prominent veins, and rounded 3-4-valved capsules.
Native Area: It extends across northern North America from Alaska southeast across arctic Canada right to the northern limit of the tree line south and eastwards to Newfoundland and the northeastern USA, with numerous disjunct populations in mountains throughout the northern USA
USDA Growing Zones: 1 – 5
Average Size at Maturity: 50 – 80 ft (to 120 ft) tall, 20 – 50 ft spread
5. Western Balsam Poplar (Populus trichocarpa)
Western Balsam Poplar is a tall tree with a straight narrow crown with ascending-spreading branches, grayish-brown deeply grooved bark, and coarse reddish-brown twigs aging to gray and usually hairy.
Winter buds are red, sparsely hairy to hairless, with abundant fragrant red resin.
Leaf stalks are rounded or slightly flattened, often swollen at the base, usually about ½ the leaf length.
Leaves are somewhat triangular or narrowly egg-shaped to heart-shaped, 1.2 – 5.9” long, ½ – ⅔ as wide, with a rounded, heart-shaped, or wedge-shaped base, acute tip, and finely crenate-serrate margins. The lower surface is lightly hairy, whitish to grayish-white, with red resin stains. The upper surfaces are shiny dark green.
Catkins are short-stalked, densely 10 – 90-flowered, and 1.4 – 4” long. Male flowers have numerous stamens. Female flowers have 2 – 4 plate-like spreading stigmas.
Capsules are round, 0.24 – 0.35”, densely hairy to hairless, and 3-4-valved.
Other Common Names: California Poplar, Black Cottonwood
Identifying Features: Western Balsam Poplar has grayish twigs that are often densely hairy, red winter buds with abundant fragrant red resin, leaf stalks that are flattened or rounded with a swollen base and half the length of the leaf, variably shaped leaves with rounded to heart-shaped bases and whitish lightly hairy lower surfaces with red resin stains, and 3-4-valved capsules. It is mostly confused with Balsam Poplar, which has prominent veins on the lower leaf surfaces and egg-shaped, two-valved capsules, or with Quaking Aspen (Populus tremuloides), but that one usually has white bark that always remains smooth and has only slightly resinous buds.
Native Area: Western North America from southeast Alaska south to northern Baja California, Mexico, east to the Rocky Mountains of Canada and the USA
USDA Growing Zones: 3 – 8
Average Size at Maturity: 40 – 165 ft tall, 20 – 40 ft spread
6. White Poplar (Populus alba)
White Poplars are tall, fast-growing trees that sucker freely and have a broad crown with somewhat ascending branches, twigs that are green or brownish, rounded, and white tomentose when young.
Leaves are dimorphic, roughly egg-shaped, 1.6 – 4” long, green above and white below, with somewhat flattened leaf stalks the length of the leaves.
Leaves may be shallowly lobed or irregularly toothed or notched and tomentose on both surfaces. Other leaves are deeply palmately 3-5-lobed with a much longer middle lobe than the lateral ones, and they become less tomentose as they mature.
Buds are small, russet-colored, egg-shaped, densely white tomentose maturing to shiny.
Male catkins are 1.2 – 2.4” long, and the flowers have 8 – 10 stamens.
Female catkins are 2 – 4” long, with stalked flowers with two-lobed stigmas.
It’s highly invasive and introduced in almost every US State and most of southern Canada.
Other Common Names: Silver Poplar, Silverleaf Poplar, European White Poplar
Identifying Features: White Poplar has strongly dimorphic and tomentose leaves that make it hard to mistake it for other poplars or members of its genus. One of its leaf types is deeply palmately 3-5-lobed and somewhat tomentose, while its other leaves are roughly egg-shaped green above and white below and tomentose on both surfaces, plus its twigs are also tomentose when young, as are their winter buds until they mature. It could be mistaken for the Gray Poplar, but that one has gray tomentose leaves that are coarsely toothed but never lobed.
Native Area: Central, southern, and eastern Europe, Mediterranean islands, temperate Asia, northern Africa
USDA Growing Zones: 3 – 8
Average Size at Maturity: 40 – 80 ft (to 100 ft) tall, 40 – 50 ft spread
7. Gray Poplar (Populus × canescens)
Gray Poplar is a natural hybrid of the White Poplar and the European Aspen, both native to Europe.
As a hybrid, many characteristics are intermediate between its parent strains. However, it’s an incredibly vigorous hybrid that is larger than either of its parents, reaching 130 ft tall with a trunk 5 ft or wider.
Its bark can be grooved like poplar or smooth like aspen.
It has slightly narrower leaves than either parent, which are dull green above and silvery gray-green below.
It differs from White Poplar in having leaves that are coarsely toothed but never lobed and gray tomentose when young but become mostly hairless with age.
It is said to escape cultivation rarely and isn’t considered invasive, yet it’s introduced in 27 countries worldwide.
Most cultivated trees are male, but females naturally occur and produce fertile seeds.
Other Common Names: Narrowleaf Cottonwood, Mountain Cottonwood
Identifying Features: Gray Poplar is a hybrid between the White Poplar and European Aspen, so it has many characteristics that are intermediate between the two, including bark that could be grooved like poplar or smooth like aspen. However, it differs in being much taller at up to 130 ft with a wider trunk of up to 5 ft, and it has narrower leaves that are dull green above and silver-gray below, coarsely toothed but never lobed, and are gray tomentose instead of white.
Native Area: Europe, Western Asia
USDA Growing Zones: 4 – 9
Average Size at Maturity: 65 – 130 ft tall, 30 – 50 ft spread
8. Simon’s Poplar (Populus simonii)
Simon’s Poplar are medium-sized trees with relatively narrow trunks (to 1.65 ft), a somewhat rounded crown, and grayish-green bark that becomes dark gray and grooved when mature.
Twigs are russet and conspicuously angled but become yellowish-brown, rounded, slender, and smooth with age.
Buds are sticky brown and elongated with long-pointed tips.
Leaf stalks are rounded, yellowish-green or reddish, and shorter than the leaf.
Leaves are variously diamond-shaped, broadest above the middle, 1.2 – 4.7” long, with a wedge-shaped to obtuse or narrowly rounded base and an acute to long-pointed tip. Lower surfaces are grayish-green to whitish, while upper surfaces are shiny bright green.
Male catkins are 0.8 – 2.8” long with greenish bracts and 8 – 9(-25) stamens per flower.
Female catkins are 1 – 2.4” long and have flowers with two-lobed stigmas.
Capsules are small, hairless or lightly hairy, and 2(3)-valved.
Other Common Names: Simon Poplar, Chinese Cottonwood
Identifying Features: Simon’s Poplar has young twigs that are conspicuously angled, sticky brown buds with long-pointed tips, yellowish-green to reddish rounded leaf stalks that are shorter than the bright shiny green, variously diamond-shaped leaves that are broadest above the middle and grayish-green to whitish below. It is sometimes mistaken for Black Poplar, which has ciliate margins on its leaves, a flattened leaf stock, purplish anthers, and larger two-valved capsules.
Native Area: Northeast China, Mongolia
USDA Growing Zones: 2 – 5
Average Size at Maturity: 30 – 65 ft tall, 10 – 30 ft spread
9. Chinese Necklace Poplar (Populus lasiocarpa)
Chinese Necklace Poplars are medium-sized trees with conical to rounded crowns and narrow trunks (to 1.6 ft) with dark gray grooved bark.
Twigs are yellowish-brown or purplish-brown, robust, angled, and usually hairy or sometimes smooth with age.
Buds are large, roughly egg-shaped, and somewhat sticky, with a tomentose basal scale.
Leaf stalks are red, rounded, pilose-hairy, and 2 – 3.1” long.
Leaves are heart-shaped to egg-shaped, with deeply heart-shaped to earlobe-shaped bases and long or rarely short-pointed tips. They’re 6 – 12” long, greenish with tomentose veins on lower surfaces and bright green and mostly hairless above with a downy-hairy base. Margins are glandular crenate-serrate toothed and revolute.
Male catkins are 3.5 – 4.7” long with pilose-hairy rachis and numerous stamen per flower.
Female catkins are 6 – 9.4” long with a pilose-hairy rachis.
Capsules are egg-shaped, three-valved, tomentose, 0.4 – 0.7”, and short-stalked to stalkless.
Other Common Names: None
Identifying Features: Chinese Necklace Poplar has quite large, 6 – 12”, often heart-shaped leaves with heart-shaped to earlobe-shaped bases, pointed tips, tomentose veins on the lower surface, and revolute crenate-serrate margins. They also have large, somewhat sticky buds with tomentose basal scales and tomentose three-valved relatively large 0.4 – 0.7” capsules. It can be differentiated from the closely related Wilson’s Poplar by its pilose-hairy leaf stalks, buds with tomentose basal scales (as opposed to hairless), and its deeply cordate to earlobe-shaped leaf bases.
Native Area: Temperate areas of central China
USDA Growing Zones: 7 – 10
Average Size at Maturity: 40 – 60 ft tall, 30 – 45 ft spread
10. Laurel Leaf Poplar (Populus laurifolia)
Laurel Leaf Poplar is a medium-sized tree with a wide and rounded crown, grayish bark that is grooved and darkens towards the base, and twigs that are yellowish, angular, and tomentose (rarely hairless).
Buds are conical and very sticky with tomentose basal scales.
Leaves are dimorphic and elliptic, variously egg-shaped to lance-shaped, 2.4 – 5.9” long, with a rounded or wedge-shaped base, acute to long-pointed tip, and a finely round-toothed margin that is ciliate. Leaf stalks are often tomentose and channeled on the upper surface.
Male catkins are 1.2 – 1.6” long, with small deciduous bracts, and there are numerous stamens per flower with purplish-red anthers.
Female catkins are 2 – 2.4” long and have a tomentose rachis.
Capsules are hairless to pilose-hairy, egg-shaped, 2-3-valved, and 0.22” long.
Other Common Names: Laurel Poplar, Bitter Poplar
Identifying Features: Laurel Leaf Poplar has dimorphic, elliptic, egg-shaped to lance-shaped leaves with finely rounded-toothed margins that are ciliate, usually tomentose and channeled leaf stalks, very sticky conical buds with tomentose basal scales, male catkins with purplish-red anthers, and sometimes pilose hairy, egg-shaped, 2-3-valved capsules. It is sometimes mistaken for Balsam Poplar with its sometimes similar-looking leaves, but that one has red resin stains and prominent veins on its lower leaf surfaces and long, shiny, reddish buds that are not tomentose and have very fragrant red resin.
Native Area: Kazakhstan, the Altai, Mongolia, and Xinjiang in China.
USDA Growing Zones: 4 – 8
Average Size at Maturity: 40 – 50 ft (to 70 ft) tall, 20 – 30 ft spread
11. Wilson’s Poplar (Populus glauca ‘wilsonii’)
Wilson’s Poplar is often called Populus wilsonii, but that name is a synonym.
They’re medium to tall trees with trunks to 5 ft wide, broadly columnar to spreading crowns with bare lower trunks, and dark grayish-brown bark that is slightly grooved and exfoliating.
Twigs are purple or dull brown becoming grayish-brown, rounded, and pilose-hairy.
Buds are russet or purplish brown, egg-shaped to roundish, large, hairless, and somewhat sticky.
Leaf stalks are purplish or reddish, rounded, as long or longer than leaves, hairless, and sometimes glandular.
Leaves are broadly egg-shaped to almost rounded, 3.1 – 7.9” long, with heart-shaped to rounded-truncate bases, obtuse tips, and glandular round-toothed margins. Lower surfaces are grayish-green with raised purplish or reddish midribs and are tomentose maturing to hairless. Upper surfaces are bright bluish-green with often pilose-hairy veins.
Male catkins are 2 ¾” long, and female catkins are 6” long with downy-hairy rachis.
Other Common Names: None
Identifying Features: Wilson’s Poplar has dark gray, only slightly grooved and exfoliating bark, rounded pilose-hairy twigs, long reddish or purplish rounded leaf stalks that are sometimes glandular, and broadly egg-shaped to roundish leaves with obtuse tips, purplish or reddish midribs, and glandular round-toothed margins. It can be distinguished from the closely related Chinese Necklace Poplar by its pilose-hairy twigs, hairless leaf stalks, and bright green leaves with a purplish or reddish midrib and stalk.
Native Area: Tibet to Central China
USDA Growing Zones: 5 – 9
Average Size at Maturity: 60 to 80 ft tall, 20 – 30 ft spread
12. Desert Poplar (Populus euphratica)
Desert Poplars are medium-sized trees with conical to spreading, open and rounded crowns, grayish-brown to olive-brown thick grooved bark on thick (to 8 ft), and often forked and crooked trunks.
Twigs are slender, brownish, pilose when young, then finely tomentose to hairless.
Buds are brown, ellipsoid, 0.28”, and hairy, becoming hairless.
Leaf stalks are about as long as the leaf. Leaves are somewhat linear with variable margins when young becoming variously egg-shaped, rounded, kidney-shaped, to somewhat triangular, with a wedge-shaped, rounded, or truncated base and a tip with large coarse teeth or small lobes when mature.
Male catkins are slender, rounded, 0.8 – 1.2” long with a finely tomentose rachis and purplish-red anthers.
Female catkins are 1” with a finely tomentose or sometimes hairless rachis. Their flowers have three yellowish-green, two-lobed stigmas.
Capsules are 0.4 – 0.5”, hairless, and 2-3-valved.
Other Common Names: Euphrates Poplar, Diversiform-leaved Poplar, Firat Poplar, Salt Poplar
Identifying Features: Desert Poplar has a thick, often forked, and crooked trunk with thick grooved bark, ellipsoid buds, variably shaped dimorphic leaves with margins that have coarsely toothed or lobed tips when mature with smooth bases, purplish-red anthers on male catkins and three yellow-green two-lobed stigmas on female catkins with 0.4 – 0.5” hairless 2-3-valved capsules. It can be mistaken for Gray Poplar, but it is a much larger tree with gray shallowly grooved bark and gray tomentose young leaves.
Native Area: North Africa east across the Middle East and Central Asia to western China
USDA Growing Zones: 5 – 9
Average Size at Maturity: 40 – 50 ft tall, 30 – 50 ft spread
Growing poplar trees can be a good choice if you are in need of a fast-growing tree to provide shade or privacy in a hurry. They are often planted along with other slow-growing, longer-lived trees to fill the space until the other trees can reach a mature age.
However, some poplar trees are known to be quite invasive, and many hybridize readily with wild native stock. For this reason, it is best to choose a poplar that is native to your area, then you don’t have to worry about it invading nearby areas or hybridizing with our wild stock.
Just like with any tree, it is important to do a little research to ensure your poplar establishes successfully.
In addition to understanding the USDA Planting Zones, you must check your chosen tree’s soil, light, and moisture requirements and compare that to your site. Check out How to Pick A Tree For Your Yard for more information on choosing the right tree for the right spot in your yard.
Some poplar trees are adapted to cold and cool temperate climates and will not do well in climates above USDA 6, while others are adapted to warm temperate climates and will not do well in climates below USDA 6.
Most poplar trees tend to prefer full sun, and while some tolerate partial shade, none will do well in full shade.
Poplars tend to do best in consistently moist soil that is rich with lots of organic matter. Some will even tolerate seasonally water-logged soils, while others require better drainage.
Poplar trees are some of the fastest-growing trees in the world, frequently growing up to 6 ft in a single year. The fastest growing, Superior Hybrid cultivar of Populus x canadensis grows to 8 ft in one year.
With their rapid growth, they tend to be quite short-lived trees. The shortest-lived species reach a maximum age of 30 – 50 before they die, with trees living to only twenty years not uncommon.
The longest-lived true poplar (not counting the Tulip Poplar from the Magnoliaceae family!) is the Balsam Poplar which lives about 100 years, or sometimes up to 150 years.
Poplar wood is often used for biofuel, pallets, plywood, and furniture.
Poplar bark, leaf, and dried, unopened leaf buds are used worldwide to make medicines for coughs, colds, and hemorrhoids and as an antiseptic first aid treatment for treating wounds.
Balsam Poplar and Western Balsam Poplar are widely used in the popular Balm-of-Gilead salve made by herbalists and alternative medicine enthusiasts. The buds are collected in the spring, then infused into oil at a low heat (crockpots on low heat work great for this), and then the oil is strained and made into a salve using beeswax. If you harvest any buds, be sure to follow the rules of ethical wildcrafting to ensure there is plenty left for the tree’s growth, for wildlife that may feed on them, and for other humans to enjoy!
Poplars have been used successfully in numerous different ecological restoration projects where soil and water have been contaminated. They also are great in forest restoration, where they need to quickly regrow stretches of forest to regain connectivity between isolated patches. They are always planted alongside other slow-growing trees that will replace the poplars as they die off, providing long-term restoration of connectivity.
Poplars provide cover and habitat for numerous birds, squirrels, bears, porcupines, deer, elk, and more.
Numerous moths and butterflies feed on the leaves of poplars in their larval stages.
Now you can use your newfound skills to go out and identify the poplars around you! Can you tell which ones are native and which are introduced, and if you have really developed your skills well, can you even spot the hybrids around you?
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Lyrae grew up in the forests of BC, Canada, where she got a BSc. in Environmental Sciences.
Her whole life, she has loved studying plants, from the tiniest flowers to the most massive trees.
She is currently researching native plants of North America and spends her time traveling, hiking, documenting, and writing.
When not researching, she is homeschooling her brilliant autistic son, who travels with her and benefits from a unique hands-on education about the environment around him.