The effects of frosts on seed production in subterranean clover (Trifolium subterraneum)

Abstract

Six cultivars of subterranean clover, Geraldton, Yarloop, Woogenellup, Clare, Mount Barker, and Tallarook, were grown as ungrazed swards at 1,700 feet a.s.1. in the Mackenzie Country of South Canterbury, New Zealand. In this very frosty environment seed yields tended to increase with increasing lateness of flowering although Clare and perhaps Tallarook appeared to be more frost susceptible than the other cultivars. It is suggested that the deleterious effects of frosts in reducing the seed yields of subterranean clover may have been overemphasized in the past and that the trend for seed yields to increase with increasing lateness of flowering can be partially explained by differences in runner production.