Towards improving white clover establishment on farms

Abstract

The establishment of new clover-based pastures takes a full year and has two distinct components; seedling emergence from sowing, and subsequent grazing management. A Ministry of Agriculture and Forestry (MAF) Sustainable Farming Fund (SFF) project to investigate the causes of inconsistency of white clover establishment concluded this came primarily from a lack of knowledge of white clover in both sowing and grazing management skills, and reflected how far modern farming technology has moved away from clover-based systems towards nitrogen (N)-boosted systems in recent years. Typically, less than half the seed being sown emerges, for both ryegrass and clover, although good results do occur. A trial looking into seedbed conditions on a dairy farm highlighted the importance of good seedbed consolidation in order to accurately control sowing depth, lifting white clover emergence by 50% and ryegrass by 25% using a roller drill. Consolidation did not affect emergence using a triple disc drill, but it did improve quality of sowing by reducing soil drag and spill by the rear coulters causing excessive burial of the front coulters rows. Differences in emergence were still evident in the performance of the clover in the following summer with 14% clover in the areas that had been hard rolled compared to 4% where it had not. In another trial on a hill soil of lower N fertility status, the taking of hay crops in the first summer, not a normally recommended practise, enhanced clover establishment compared to rotational grazing all year. The roles of clover, N fixation and quality feed, are discussed in the context of how and where clover may fit into modern farm systems. Keywords: emergence, establishment, grazing management, seedbed preparation, sowing methods, white clover