Forest Preserve District of Cook County, Illinois
Nature Bulletins
Newton Home Page

Introduction and Instructions

Search Engine

Table of Contents



Nature Bulletin No. 185-A   March 27, 1965
Forest Preserve District of Cook County
Seymour Simon, President
Roland F. Eisenbeis, Supt. of Conservation

On the east bank of the DesPlaines River, a short distance from the beginning of an old portage route across to the North Branch of the Chicago River, stand three giant cottonwoods. They mark the site of a pioneer's cabin. In our cities and suburbs, most cottonwoods -- planted for quick shade -- have been removed because their moisture-seeking roots tend to clog drains and sewers, their brittle branches break in storms, and their flying cottony seeds are "messy". But we who are prairie-bred have a soft spot in our hearts for the cottonwood. We gratefully remember resting in a shade, the rustle of its leaves announcing any vagrant breeze, and the drifting "summer snow" of its tiny seeds, each air-borne by a tiny parachute of gossamer.

On the western plains where streams were few, a belt of green cottonwoods and their close relatives, the willows, marked each watercourse -- the only trees in that dry land, Cottonwood logs were used for cabins, corrals, forts and the stockades around them. The early settlers planted cottonwoods around their homesteads because they were so easily started by cuttings from another tree and grew so quickly where few other trees could endure. The plains Indian used cottonwood roots for starting fire by friction and, according to legend, got the idea for his teepee by twisting a cottonwood leaf between his fingers, producing a cone.

Except for the Northern Black Cottonwood of the Pacific Northwest, and the Virginia Cottonwood, which sometimes attain a diameter of 7 or 8 feet, our Eastern Cottonwood is the largest of the poplar family: the willows, the aspens, the balsam poplar, the cottonwoods and related varieties, including some European species such as the Carolina and Lombardy poplars. Our older cottonwood trees, frequently 3 or more feet in diameter, have wide-spreading crowns supported by massive trunks -- sometimes tall, straight and cylindrical, frequently divided near the ground. The thick ash-gray bark is deeply furrowed on old trees; smooth and greenish-yellow on saplings .

Like the aspen, the foliage of a cottonwood trembles in a breeze. Its leaves are attached to a stout twig by flattened stems, so that the slightest breath of air sets them to trembling and the tree seems to twinkle and beckon in the sunlight. Its thick leaves, broad at the base, roughly triangular and tapering to a long pointed tip, have rounded saw-teeth along the outer edges. Shiny green above and paler underneath, they become pale yellow in autumn.

The leaf buds, slender and sharp-pointed, and the flower buds, larger and plumper; are covered with a fragrant resin gathered by bees for beeswax. The male and female flowers are borne on separate trees. The male flowers are reddish-purple catkins from 3 to 5 inches long. When they have shed their pollen and fallen to the ground they look like big red caterpillars. The female flowers are catkins resembling strings of green beads. Each bead is a pod and in summer, when they open, the seeds within them sail away, each on its parachute of fine white down, and everything in the neighborhood will be covered with fuzz. Hence the name "cottonwood".

Its wood is very light, soft, weak, fine-grained, whitish and, although not durable, useful for making crates, woodenware and cheap barrels. Its principal uses are for making excelsior and paper pulp.

The Greeks had a saying: "Poplar leaves, like women's tongues, are never still. "

To return to the Nature Bulletins Click Here!
Hosted by NEWTON

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Sponsered by Argonne National Labs