Effect of ground cover and tussock proximity on legume establishment

Abstract

Five areas, on a gradient from dry hygrous to hygrous vegetated upland high country yellow-brown earths, were broadcast oversown with four legumes. Position and weight of plants were assessed in relation to major ground cover types, and to distances and direction to nearest tussock. The ratios of actual to expected numbers of plants, and actual to mean weights, measured the favourability of particular types of microsite. Interactions between tussocks and other resident vegetation were generally not significant. Ground cover and tussock proximity had greater effect on initial establishment position than on subsequent growth. Legume establishment was high adjacent to tussock on the most arid site, but on more hygrous sites establishment was high in inter-tussock spaces. Plant weights were generally greatest away from tussocks. Bare soil gave low establishment and plant weights. Raoulia and Gaultheria spp. provided the best cover sites for establishment. Red clover had high preference for microsites near tussock on the most arid site, and lotus in higher preference for bare soil on the wettest site.