Grazing management for regeneration of balansa clover in a cocksfoot pasture

Bolta’ and ‘Frontier’ balansa clover seedlings were counted through two autumns following a large seed set in November 2006, from monocultures sown in a dryland environment in Canterbury. Following rain on 5 January 2007, 65% of ‘Bolta’ seed and 54% of ‘Frontier’ seed emerged. Approximately 11% of seed produced in 2006 remained in the soil in April 2008. These results highlight the regeneration potential of balansa clover. In a separate dryland grazing experiment at Lincoln University, six ‘Bolta’ balansa clover/cocksfoot plots were managed individually during five spring flowering periods to provide different amounts of seed. The total annual dry matter production of the balansa clover was dependent on this grazing management. Specifically, clover content in those cocksfoot pastures averaged above 30% for the 3 years following a major seeding event. Closing the balansa clover/cocksfoot pasture on 6 September to allow flowering after a February sowing, or no spring grazing after a late May sowing, provided sufficient seed for successful re-establishment of the balansa clover for the next 3 years. In contrast, when the February sown plots were closed on 24 October, only half as much clover was produced in the following years. Thus, successful regeneration of balansa clover will require management for seed production in the establishment year and then on a 3 year cycle.