Under the conditions of the experiments reported, trifluralin, nitralin, DCPA, bensulide and two commercially unavailable compounds were safest on young grape vines. Fair to good weed control was obtained at safe rates except where resistant weed species were present. Shallow incorporated trifluralin will control weeds at 1/2 to 1 lb per acre rates, and will prove useful for weed control in grape nurseries; however, care should be taken to follow the labeled rates and directions for incorporation. Combinations of the grass herbicides such as trifluralin, nitralin, DCPA, diphenamid and bensulide with simazine and several new herbicides for broadleaf weed control are being studied further.

Assistance was provided by Jack Farrior, formerly of Paul Masson; Robert Thompson of DiGiorgio; B. Stribling, Stribling's Nursery, Merced; V. Carlson and L. Hendricks, both Farm Advisors in Merced County; Curtis Lynn and Don Rosedale, Farm Advisors in Fresno and San Diego counties respectively; Al Baber, formerly Farm Advisor, Monterey County; Jim Yeager, Lloyd Lider, and Clyde Elmore of the Department of Botany, U.C., Davis; and Norman Ferrari of the Viticulture and Enology Department, U.C., Davis. This work was supported in part by grants-in-aid from Geigy Chemical Company, Eli Lilly Chemical Company, and Diamond-Shamrock Chemical Company.