Nature Bulletin No. 185, March 26, 1949
On the Banks of the Des Plaines 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. Nearby is a dead misshapen tree, much older but much smaller because, when a mere sapling, it was bent by the Indians to mark their trail to the Winnebago country.
In 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 seeds are "messy". But we who are prairie-bred have a soft spot on our hearts for the cottonwood. We gratefully remember resting in its shade, the rustle of its leaves announcing any vagrant breeze, and the drifting summer snow of its tiny seeds, each airborne 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 that few other trees could endure. The plains Indians used cottonwood roots for starting fire by friction and, got the idea for his teepee by twisting a cottonwood leaf between his fingers, producing a cone. Indian children still make "play" teepees in this way.
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. The 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, and 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 set 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 turn 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 with a parachute of fine white down, and everything in the neighborhood will be covered with this fuzz. Hence the name "cottonwood".
Its wood is very light, soft, weak, fine-grained, whitish, and not durable, and is used for crates, woodenware, and barrels. Its principal uses are for making excelsior and paper pulp.
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