VIABILITY OF AXILLARY BUDS OF WHITE CLOVER (TRIFOLIUM-REPENS) IN GRAZED PASTURE

Stolon nodes of white clover were sampled monthly for 18 months from continuously grazed (set stocked) and rotationally grazed pastures in New Zealand. Both pastures were stocked at 22.5 ewes plus lambs/ha. Axillary buds were classified into viability categories using an incubation technique. On average, 54 % of nodes had non-viable or dormant buds, 25 % had axillary buds that were viable but non-active and 0.1 % bore reproductive buds. Although 21 % of buds emerged, only 8.5 % of nodes bore live branches. Bud activity was strongly inhibited during the spring period of both years and this inhibition could not be removed by incubation. The greatest bud viability occurred at node 4 (from the apex) although 30-40 % of the buds at this position were non-viable. This pattern of variation changed somewhat with season. Some viable buds were present at nodes more than 20 from the apex but these were of low vigour. Secondary stolons had different patterns of bud activity from those of primary stolons until they comprised more than 16 nodes.