Wyoming State Tree
Plains Cottonwood (common name) Populus deltoides ssp. monilifera (scientific name) Overview Plains cottonwood was chosen as the state tree for Wyoming in 1947. The choice was inspired by the presence of a huge specimen, approximately 50 feet tall, growing on a ranch near Thermopolis, Wyoming. At 50 feet tall and 29 feet around, it was thought to be the largest cottonwood in the world until it burned down in 1955. Cottonwoods are by nature short-lived trees when they eke out an existence on the Great Plains. In 1961, Wyoming amended its state tree statute when it was discovered that the original legislation did not list plains cottonwood's Latin name to specify Populus sargentii as the state tree. Plains cottonwood has undergone several name changes, and currently most botanists consider Populus sargentii not to represent a distinct species, but rather a subspecies of the eastern cottonwood. Plains cottonwood's currently accepted scientific names are Populus deltoides ssp. monilifera or Populus deltoides var.occidentalis. It also has several alternate common names: Texas cottonwood, river cottonwood, western cottonwood, and plains poplar. Close-up STATUS Official PHYSICAL DETAILS Plains cottonwood is a stout, wide-branching tree. Its large, wide, simple leaves are somewhat triangular in shape, often shiny, with pale to bright red veins. They turn yellow-gold in fall. Its flowers grow in cylindrical groups, followed in spring by tiny seeds with tufts of cottony hairs. Height: 10-98 ft (3-30 m) Diameter: 5-79 in (13-200 cm) Bark: young: green-yellow, smooth mature: dark gray, thick, rough and deeply furrowed Seed: inch-long with capsules containing 3-4 valves, many tiny, cotton-like seeds inside valves Leaves: large and triangular with coarse teeth LIFESPAN Plains cottonwood is a quick-growing, short-lived deciduous tree. It is considered the fastest-growing tree in the Great Plains. The life expectancy is about 70-100 years. HABITAT Plains cottonwood's range is dry subhumid to semiarid, with extremes and rapid fluctuations in temperature, unpredictable and limited precipitation, frequent and cyclic droughts, and strong persistent winds. Average temperatures in plains cottonwood's range vary from -50°F (-46° C) to 115° F (46° C). IMPORTANCE TO LIVESTOCK AND WILDLIFE Plains cottonwood stands provide roosting and nesting sites, nesting material, and feeding sites for the majority of all birds breeding in northeastern Colorado. Beavers use the wood of plains cottonwood for food and for buildings dams and lodges. The plains cottonwood/red-osier dogwood community provides thermal cover, debris recruitment, and streamside stability for fishes. Plains cottonwood is eaten by prairie porcupines and is the most important browse species for mule deer in the fall. In Colorado, plains cottonwood groupings are used by fox squirrels for nesting and feeding. Plains cottonwood forests provide nesting sites for eagles, hawks, and other birds. OTHER USES AND VALUES This species is not considered to be commercially valuable. The wood is not durable when exposed to soil and other moist conditions. It is used for rough construction lumber, temporary fence posts, corral poles, fuel, veneer, boxes, crates, plywood, excelsior, and wood pulp. It is planted as a windbreak. Plains cottonwood, the "Pioneer Tree of the Plains," is often the only tree found in the expanses of plains in the western United States. It is a sure sign of water and welcome shade. America's early pioneers used the tree's leaves as food for their livestock and its timber to build dwellings and dugout canoes. The bark was used to make a bitter, medicinal tea. In regions with few trees, the very noticeable cottonwoods often served as gathering places, landmarks, and sacred objects for several Plains tribes. Plains Indians also used the wood for a variety of purposes from toys to teepee poles, and its roots to start fires. The teepee pattern is supposedly patterned after the deltoid leaf shape. The Teton Dakota ate the inner bark and the Omaha used it to make the Sacred Pole. Nebraska tribe children made toys with the leaves and made gum and play jewelry from the fruits. REPRODUCTION Plains cottonwood does not readily form suckers or stem sprouts, and sprouting is uncommon except in flood-trained shoots. It is generally killed by fire and has very poor sprouting response. SITE CHARACTERISTICS Wyoming's state tree is found on bottomlands, subirrigated valleys, floodplains, and small sandbars in riverbeds. It is found next to springs that flow long enough to form ponds. Plains cottonwood is susceptible to drought except where water tables are high; drought-induced mortality can be high. The tree is a dominant species in Montana, North Dakota, Wyoming, and Manitoba.  LOCATION/ELEVATION Plains cottonwood grows in central Canada, south through the Great Plains in North Dakota, South Dakota, Nebraska, and Kansas, into western Oklahoma, north central Texas, and extreme northeastern New Mexico, and north to Colorado, eastern Wyoming, and eastern Montana. The eastern limit of the range is not well defined because it integrates with the western limit of the range of the typical variety, eastern cottonwood. Its elevation range is 1,000 to 9,000 feet (300-2,743 m). TRIVIA Distinguishing among the various types of cottonwoods, Meriwether Lewis's journal entry from July 2, 1806 includes the following: "leaf of the cottonwood on this river [Bitterroot] is like that common to the Columbia narrower than that common to the lower part of the Missouri and Mississippi [plains cottonwood] and wider than that on the upper part of the Missouri [narrow-leaved cottonwood]."
	Click to enlarge an image Plains Cottonwood Plains Cottonwood Leaf Plains Cottonwood Seeds Plains Cottonwood Bark Plains Cottonwood Distribution Map (pdf) CLASSIFICATION Kingdom: Plantae Subkingdom: Tracheobionta Superdivision: Spermatophyta Division: Magnoliophyta Class: Magnoliopsida Subclass: Dilleniidae Order: Salicales Family: Salicaceae Genus: Populus L. Species: Populus deltoides  Subspecies: Populus deltoides ssp. monilifera
	Data Sources: U.S. Forest Service U.S. National Arboretum U.S. Department of Agriculture Author: World Trade Press