Abstract
An experiment is described in which the performance of two white clover varieties, ‘Grasslands 4700’, and ‘Grasslands Huia’, was compared in separate pastures containing ‘Grasslands Ariki’ ryegrass, under two grazing intensities. Establishment, productivity, and botanical composition were measured for a 16-month period from an autumn sowing. There were no significant differences in germination and establishment of the two clover varieties. There was no difference in yield between the two clover varieties during the first 9 months (sowing to mid summer). During the following autumn and winter 4700 clover yielded more than Huia clover. Yields of ryegrass in association with 4700 clover were reduced. In the second winter 4700 clover suppressed ryegrass more severely than at any other period of the experiment. Conversely Huia clover was suppressed by the ryegrass. In the second winter 4700 clover suppressed ryegrass more severely than at any other period of the experiment. Conversely Huia clover was suppressed by the ryegrass. The results are discussed in relation to the effects of the two clover varieties and grazing frequency on the production and botanical composition of the pastures, with special reference to interspecies competition for nitrogen and light as influenced by weather.