Effects of Cultural and Management Practices on Seed Production of ‘Plains’ Bluestem

Abstract

Seed production of 'Plains' bluestem (Bothriochloa ischaemum [L.] Keng.) is difficult to assess because of its indeterminate flowering habit and its vegetative canopy which, when excessive, interferes with seed harvests. The variety will produce two seed crops annually. The first matures in July and the second, if managed properly, in October. The effects of three management treatments on the amount of forage associated with each seed crop were highly significant in 2 out of 3 years. The study suggests that a delay of about 21 days in removing the residual forage remaining after the summer seed harvest will favorably influence fall seed yields. Where nitrogen was applied, the decline in vegetation associated with the seed crop was directly related to the previous year's forage cropping practice. Burning residual litter in early March, fertilizing with a 60-45-0 (N, P, K) pound rate of N and P was best for the production of a summer seed crop. The removal of residual forage by mowing and baling about July 29, cultivation, fertilization, and irrigations as needed, favorably influenced fall seed yields. The combined yield of the two crops in 1969 was in excess of 200 lb/acre pure seed.