Two experiments were conducled to estimate the influence of initial cutting dates in March and April and of cutting frequencies on Guinea grass, elephant grass and star grass productivity. Increasing delay in date of first cut in the season resulted in a progressive increase in dry-matter yield. 72-81% of the tiller population at any cut were vegetative and this helped to maintain good aftermath yield for each date of first cut. Early April cuts gave the highest dry-matter yield and early March the least.Harvesting frequencies affected the sward productivity such that the annual dry matter yield increased with increasing harvesting interval from 6800 kg ha"' for a 3-week interval to 13,000 kgha"' fora 10-week interval. The proportion of green leaf in the dry matter dropped from Sl-T/â t 3-week intervals to 32 0% at 10-week intervals. Seasonal effects showed that potential yield was reduced by a short interval between harvests early in the season but not late in the season. Species differences in quality and in the harvesting interval that gave the maximum yields were noted. These results are discussed in relation to management of the sward throughout the growing season.

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The effects of seasons on size, number and area of the dung deposited on a grazed paddock were examined. Rate of dung breakdown, herbage fouling, and rejection were also investigated. Significant seasonal differences were found in number, size, area of dung and in proportion of paddock fouled per grazing such that these values were higher in wet than in dry season. A higher breakdown rate was obtained in the dry season when the termites were the main degradation agents than in the wet season when the dung was degraded mainly by the copriphilous fungi. The herd rejected the fouled herbage for a longer period during wet season than during the dry season. Two breakdown patterns for the dry season (depending on the presence of termites in the ecosystem) were suggested. Herbage rejection was discussed in relation to animal production and range improvement.

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