Quaking Aspen

(Populus tremuloides)

General Description

Aspen trees grow fairly straight and become clear of

lower limbs over time. Sometimes called Trembling Aspen

because their leaves tremble in a light breeze due to the                                                 ir

flattened petioles. Most extensive native range of any tree

in North America. Rapidly recolonizes disturbed sites

(after fire, logging, etc.). The largest tree in North Dakota is

70 feet tall with a canopy spread of 39 feet.

Leaves and Buds

Bud Arrangement - Alternate.

Bud Color - Reddish-brown.

Bud Size - Terminal buds are conical-shaped, pointed,

lustrous, and 1/4 inch long.

Leaf Type and Shape - Simple leaves, cordate to

broad-ovate.

Leaf Margins - Margins have small rounded teeth.

Leaf Surface - Glabrous.

Leaf Length - 1½ to 3 inches.

Leaf Width - 1¼ to 2 inches.

Leaf Color - Dark green above, dull green below.

Fall color is golden-yellow.

Flowers and Fruits

Flower Type - Dioecious, staminate (male) and pistillate

(female) flowers are on different trees. Flower is a catkin.

Flower Color - Greenish when immature, turning brown.

Fruit Type - Very small cottony seeds (average 3 million

per pound). Seeds borne in a capsule.

Fruit Color - Pale green.

Form

Growth Habit - Trunk has little taper to the tip, rounded

crown with brittle branches.

Texture - Medium, summer; medium, winter.

Crown Height - 25 to 60 feet.

Crown Width - 20 to 30 feet.

Bark Color - Varies from chalky white to olive-gray, and

becomes rough furrowed on the lower trunk of mature

trees.

Root System - Roots are abundant in the top 2 to 2½ feet

of soil. Aspen usually regenerates from root suckers.

Environmental Requirements

Water

Needs a moist site to do well. Primarily present in areas

of high water table, north and east facing slopes, seeps and

other moist areas.

Light

Full sun, will not tolerate shade.

Uses

Conservation/Windbreaks

Medium tree for farmstead windbreaks, and riparian

plantings.

Wildlife

Heavily browsed by deer and other mammals as a winter

food source. Grouse utilize large male buds for food.

Agroforestry Products

Wood - Primarily used for paper, pulpwood, boxes, crates,

and pallets.

Urban/Recreational

Along ponds or streams, wetlands, and woody draws.

Allowances must be made for extensive suckering.

Pests

Common diseases include Hypoxylon canker, Cytospora

canker, and stem decay. Extracts of Populus species have

toxic effects on insect pests.

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