Highest yields of safflower were obtained when a medium pre-irrigation of 18 inches and two supplemental 8-inch crop irrigations were applied, according to the trial reported here. When approximately the same total amount of water was applied in one pre-irrigation or in a pre-irrigation and one supplemental crop irrigation, the yields were significantly lower. This study strongly suggests that maximum safflower yields (on Panoche clay loam soil) depend on readily available soil moisture in the top 4 feet of soil during bud and flowering periods.

Don A. Patterson and Jim Fisher of Boston Ranch, Westhaven, assisted in conducting this experiment.