Wyoming adopted the plains cottonwood as its state tree on February 1, 1947. The cottonwood, western meadowlark and bison are the most popular symbols of the Great Plains states, but only Wyoming and Kansas adopted all three.
It was later discovered that legislators had given Wyoming’s cottonwood an incorrect scientific name. On February 24, 1961, the state tree statute was amended, giving it the correct scientific name (Populus sargentii).
Wyoming’s state tree designation was inspired by a spectacular discovery. It was a giant cottonwood growing near Thermopolis, on the Paul Klein ranch (originally the J. M. Cover homestead). According to the amended state tree statute, the tree stood an estimated fifty feet tall. (Other sources list the height as 76 feet 11 inches and 77 feet.) It was believed to be the largest plains cottonwood in the world, until it burned in 1955.
A New Champion
As Wyoming prepared to celebrate its statehood centennial in 1990, a search for a new champion cottonwood was launched. The contest was conducted by the Wyoming Chapter of the Society of American Foresters, a professional forestry organization. The winner was located on the Flying X ranch in eastern Albany County. It measured 31 feet in circumference, stood 64 feet tall, and had an average crown spread just over 100 feet.
The previous owner of the ranch, Owen McGill, claimed to know the tree’s approximate age. He said it had been planted by an English immigrant, Arthur Dover, about four to five years after he homesteaded the land in 1885.
It is said that cottonwoods grow along nearly every creek and river in the state. Someday, one of them will doubtless tower over Wyoming’s plains
Original Senate File No. 121
State Tree
AN ACT to amend and re-enact Section 8-47, Wyoming Statutes, 1957, relating to the scientific name of the State Tree.
Be It Enacted by the Legislature of the State of Wyoming:
Scientific Name
Section 1. That Section 8/47, Wyoming Statutes, 1957, be amended and re-enacted to read as follows:
Whereas the largest cottonwood tree in the world grows on the Clyde Cover Ranch, three miles north of the City of Thermopolis, Hot Springs County, Wyoming, east of highway 20, and west of the Big Horn River.
And whereas said tree is twenty-nine feet in circumference at a point four and one half feet above the ground and is estimated to be fifty feet high.
And whereas this species of tree has given its bountiful comfort and beauty to the residents of the state and its shelter and shade to the livestock of the state from time immemorial.
It is therefore fitting and proper that the cottonwood tree be designated as the state tree for the State of Wyoming. The POPULUS SARGENTII, commonly called cottonwood tree, is hereby named and declared to be the state tree of the State of Wyoming.
Approved February 24, 1961
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