Productivity and seedling recruitment of naturalised annual clovers versus sown clovers Trifolium repens and Trifolium subterraneum

Abstract

Naturalised annual clover (NAC) species (suckling clover, cluster clover, striated clover, and haresfoot clover) are commonly present to locally abundant in summer dry hill and high country areas where white and subterranean (sub) clover abundance is limited. This field trial investigated NAC species dry matter production and seedling regeneration compared to white and sub clover. Autumn seedling recruitment was measured in response to low (75 kg/ha) or high (200 kg/ha) superphosphate (SP) application. Over two growing seasons, NAC species contributed >90% to pasture legume content while white and sub clover contributed <10%. Striated, suckling, and cluster clovers showed greater recruitment under low SP with 996, 978, and 227 seedlings/m² respectively compared to high SP with 635, 466, and 123 seedlings/m² respectively. Collectively, NAC species were superior to white and sub clover on north-facing slopes. Spreading NAC species seed via livestock dung dispersal and aerial broadcasting would further increase their contribution to total pasture DM and nitrogen input.