Residual effects of cutting and grazing on grass-clover growth.

The residual effect of cutting and grazing during the growing season was investigated in the spring and summer growth in an organic crop rotation with 1-4 year-old grass-clover mixtures of white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.) either with or without red clover (Trifolium pratense L.) and with and without slurry. The white clover mixtures had significantly higher yields in spring and summer in swards that were previously grazed compared to previously cut swards, when slurry was applied. The percentage of white clover in spring was considerably reduced by previous grazing and this caused the yield response of slurry application to be highest following grazing. A similar effect on the clover content was not found in the summer growth. With the inclusion of red clover in the sward the effect of previous management on spring yield disappeared. Red clover was very abundant under the cutting regime, while the contents were declining with grazing.