IMPROVEMENT IN SOIL STRUCTURE ASSOCIATED WITH WHITE CLOVER

Observations have been made which suggest that clover is more effective than ryegrass in developing rapid improvements in soil structure. To test this hypothesis, grass, grass/clover and clover swards were grown in undisturbed field cores. Significant differences in drainage rates and plant biomass production, and visible changes in soil structure, all supported the hypothesis that clover improves structure rapidly, but there were no significant differences in bulk density, porosity or aggregate stability between the treatments. Soil moisture characteristic curves of soil/peat/grit compost planted with grass, grass/clover or clover and grown for two years indicate that a more free-draining structure develops under clover than under grass due to a higher ratio of macro- to micropores.