Fitzsimmons, Jim P.; Burrill, L. C.; Oregon State University. Extension Service; Washington State University. Cooperative Extension; University of Idaho. Cooperative Extension System; United States. Dept. of Agriculture ([Corvallis, Or.] : Oregon State University Extension Service ; [Olympia, Wash.] : Washington State University Cooperative Extension ; [Moscow, Idaho] : University of Idaho Cooperative Extension System ; [Washington, D.C.] : U.S. Dept. of Agriculture, 1993-03)
St. Johnswort (Hypericum
perforatum), also called
Klamath weed and
goatweed, was introduced from
Europe and was found in California
about 1900. It was a
major pasture weed west of the
Cascade mountains from
Tacom ...