Germination of Range Plant Seeds at Alternating Temperatures

The germination behavior at alternating temperatures of range plants suitable for seeding semi-arid range was consistent with their behaviour at the fixed temperatures of the alternation cycle, but not with weighted mean daily temperature. Unfavorable temperatures produced a greater retardation of germination than would be expected from their relative influence on the weighted mean. Alternating temperatures did not stimulate germination in the species studied. These data support conclusions from previous work regarding low seedbed temperatures as a factor in the failure of semi-arid range seeding operations.