Wikipedia
Columbia sheep
The Columbia is one of the first breeds of sheep developed in the United States. The product of USDA and university research, it was intended to be an improved breed specially built for the Western ranges of the country (where the majority of sheep raising takes place). Beginning in 1912 in Laramie, Wyoming, Lincoln rams were crossed with Rambouillet ewes. In 1918, the foundation flock was moved to the U.S. Sheep Experiment Station near Dubois, Idaho, for further refinement. Today's Columbia is a popular breed, with heavy, white fleeces and good growth characteristics. It is one of the larger breeds, and is often used for cross breeding in commercial western flocks.