Washington, D.C.: U.S. Dept. of Agriculture, 1916.

Washington, D.C.: U.S. Dept. of Agriculture, 1918.

scientific article published in 1913

Washington, D.C.: U.S. Dept. of Agriculture, 1915.

WashingtonGovt. Print. Off.1915

scientific article

scientific article

scientific article

Agricultural College, N.M. :New Mexico College of Agriculture and Mechanic Arts, Agricultural Experiment Station,1912. | New York Botanical Garden, LuEsther T. Mertz Library

Washington, D.C.: U.S. Dept. of Agriculture, 1922.