National & State Symbols
Wyoming State Tree
(Populus deltoids occidentalis)
Adopted on February 1, 1947 - Amended: 1961.
The Plains Cottonwood, (Populus deltoids occidentalis,) was adopted as Wyoming state tree on February 1, 1947.
The plains cottonwood is a large, fast-growing, short-lived tree of the Great Plains and eastern border of the Rocky Mountains. Members of the willow family, cottonwoods are named for the cottonlike mass of hairs surrounding their seeds. They are related to poplars and aspens.
Wyoming State Tree: Plains Cottonwood
Populus is the Latin name for poplars. Deltoides refers to the triangular-shaped leaves. Occidentalis is Latin for "west." American Indians may not have distinguished the two since different names have not been identified. The Lakota know them as canyáh'u, meaning "peel off wood," and the Omaha as maa-zho.
Cottonwoods are members of Salicaceae, the willow family, along with willow (Salix spp.) and quaking aspen (Populus tremuloides ). The leaves are deciduous, alternate, simple, 3 to 6 inches (8 to 15 cm) long, triangular-shaped with serrate margins. Flowers occur in the spring before the leaves appear, they are dioecious and in hanging catkins . Fruits are 1/4 inch (.64 cm) long, 3 or 4 valved capsules. The twigs are yellowish brown and smooth. The terminal buds are long and resinous. The bark is ash-gray and divided in thick flattened ridges with deep furrows.
Plains cottonwood is native throughout the central plains from Texas to Manitoba. Cottonwood, as with willow, is a pioneer species. It is also very intolerant of competition. Cottonwoods tend to seed into a new flood plain and develop as pure, even-aged stands. As cottonwoods mature (about 50-70 years after the stand begins), they are gradually replaced by the more tolerant ash and elm.
The two greatest threats to cottonwood are fire and drought. Cottonwoods are very vulnerable to fire, light burns will kill seedlings and saplings. Hotter fires can severely injure the bark on older trees, which opens the trees up to decay. While they are moderately drought tolerant, a long-term dry spell will lead to death.
Identification of the Plains Cottonwood
The Dakota ate the sweet inner bark of young sprouts of cottonwood trees in the spring. They also fed young cottonwood branches to their horses. A dye was made from the leaf buds. The Sacred Pole, used in ceremonies of the Omaha Indians, is made of cottonwood.
2013 Wyoming Statutes
TITLE 8 - GENERAL PROVISIONS
Exerpts from: Publication of the Eastern and Plains Cottonwood fact sheet was funded by the S.D. Department of Agriculture, Division of Forestry, Pierre, SD. Source: US Department of Agriculture
All of the state trees, except the Hawaii state tree, are native to the state in which they are designated.