Hybrid Poplar

(Populus hybrids )

General Description

Many hybrid clones between Populus species have been planted in the

Northern Great Plains. Most hybrids grow very fast but often lack the

cold and drought hardiness of the native cottonwood. The most

common parent species of these hybrids are Cottonwood (Populus

deltoides) and Black Poplar (Populus nigra). These hybrids are referred

to as the P. x euramericana hybrids. Other species that have been

crossed with Cottonwood include Balsam Poplar, Japanese Poplar and

Russian Poplar.

Leaves and Buds

Bud arrangement - Alternate.

Bud Color - Varies between hybrids.

Bud Size - Varies between hybrids.

Leaf Type and Shape - Simple leaves, deltoid to lanceolate, petioles are

generally flattened.

Leaf Margins - Coarsely-dentate to entire.

Leaf Surface - Glabrous, to lightly pubescent beneath.

Leaf Length - 2 to 5 inches.

Leaf Width - 2 to 5 inches.

Leaf Color - Green to dark green; yellow fall color.

Flowers and Fruits

Flower Type - Unisexual catkins; dioecious.

Flower Color - Tiny brownish-red flowers early in spring.

Fruit Type - Dehiscent capsule.

Fruit Color - Light brown, seeds in a mass of “cotton”. Many clones

are vegetatively propagated male plants and produce no seeds or

“cotton.”

Form

Growth Habit - Upright-spreading branches but not as spreading

as cottonwood. Many clones exhibit pyramidal or columnar forms.

Texture - Medium-coarse to coarse, both summer and winter,

depending upon hybrid.

Crown Height - 40 to 60 feet.

Crown Width - 20 to 35 feet.

Bark Color - Gray-green when young, turning ash-gray and forming

darker gray, furrowed bark at maturity.

Root System - Shallow and wide-spreading, equal to or greater than

the height of the tree.

Environmental Requirements

Water

Requires a moist site. Will not tolerate drought on upland sites.

Less tolerant of moisture stress than is cottonwood. High water

table required on coarse-textured soils.

Light

Requires full sun.

Uses

Conservation/Windbreaks

Narrow-crowned, fast-growing tree in field and farmstead

windbreaks, and riparian plantings.

Wildlife

Cover and snow protection. Buds provide a source of food to birds.

Twigs and young branches make good browse. Young trees are used

for food by deer, rabbits, mice and beaver.

Agroforestry Products

Wood - Firewood, energy production biomass, pulp.

Filter Strips - Roots, stems and leaves are effective nutrient sinks.

Medicinal - Populus species are a source of salicin, used for fevers

and headaches.

Urban/Recreational

Used in windbreaks, riparian areas, as visual screens and to provide

quick tree cover.

Pests

Common diseases include Melampsora leaf rust, Septoria leaf spot

and canker, Cytospora canker, wetwood, and stem decay. Common

insect pests include poplar borer, aphids, poplar bud gall mite, poplar

vagabond aphid and poplar leaf beetles. ‘Walker’, ‘Assiniboine’,

and ‘Canam’ were selected for stem canker resistance. None are

completely resistant. Extracts of various Populus species are effective

against certain insect pests.

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