Losses of range-born lambs—in some instances as high as 90%—have resulted from severe rainstorms during the lambing season on the north coast sheep ranges. Conventional protective range shelters or barns usually are economically unfeasible because of the cost. An inexpensive, experimental polyethylene plastic shelter was tested at the Hopland Field Station in southern Mendocino County during the 1957 lambing period, when 19? of rain fell. The percentage of lambs saved that season was higher than in any previous year since the Field Station was established in 1951.

Technical advice on plastics for the experimental shelter was furnished by Dr. C. E. Staff of the Bakelite Company, which contributed the film.