Swards based on a mixture of SI 70 tall fescue and S215 meadow fescue were very early in spring, gave high yields for conservation in mid-season and, rested from mid-August, gave good grazing in November-December. Under this treatment, the tall fescue assumed dominance, and the swards were persistent and remained productive. The digestibility of the tall fescue swards was always higher than that of swards based on cocksfoot with which they were compared. During spring and autumn the former sward was better grazed by stock, but the position was reversed in mid-summer. Cattle grazing tall-fescuedominant swards made better liveweight gains than those grazing cocksfoot swards during November-December.

The effects of management on the production of winter grass wen studied of 47 site England and Wales from 1954 to 1958. Cocksfoot swards provided better grazing during December and January than perennial ryegrass. The best treatment for winter‐grass production from cockfoot swards was to rest from mid‐August, giving un application of 52 lb of nitrogen per acre at this time. Perennial ryegrass produced relatively high yields if rested from early September, but the herbage should be grazed before the end of November because of the risk of it rotting. Cocksfoot herbage in normal swards lost more weight from December to January than cocksfoot sown in wide drills. Local Factors, such as aspect, altitude and sward vigour, were generally more important than latitude in determining level of yield in December. but there were greater lovsess of dry matter from December to January in the north than in the south.

The performance of livestock, on winter grass was studied at eighteen sites in England and Wales from 1957 to 1960. Beef cattle generally gained weight while grazing winter grass. They invariably did better than similar animals overwintered on the normal feeding regime of the farms concerned. At 8 centres winter grass was utilized by dairy cows. Calculations indicated that the grass provided a valuable portion of their feed. The general condition and health of livestock grazing winter grass were satisfactory at all centres. Damage caused by poaching was largely prevented by controlled grazing. The production and utilization of winter grass had no adverse effects on sward recovery in the subsequent spring.

The effects of autumn management and nitrogenous manuring on the production of early spring grass were studied from 1954 to 1957 on farms throughout England and Wales. The most important management factor influencing spring yields was the application of spring nitrogen. In the early spring 6 to 10 lb. of dry matter were produced per lb. of nitrogen applied. Autumn nitrogen increased herbage yields in the auttimn by 8 to 17 lb. of dry matter per lb. of nitrogen applied. Italian and perennial ryegrass responded well to autumn nitrogen but it was important to graze off the extra growth fairly quickly to prevent the sward becoming too open. The yield of ryegrass swards which received spring nitrogen were very much higher if they were grazed during the previous September and October than if they had been rested during those months. In two years neither the autumn management nor alumni fertilizer appeared to influence the spring yields of cocksfoot, timothy or meadow fescue swards, in one year, however, when autumn growth was poor, autumn nitrogen and resting resulted in slightly better yields on these swards in the following spring. It is suggested that resting swards during September and October to build up “reserves” is relatively unimportant in relation to the yields of grass in the following spring.

Two levels of nitrogen application (70 and 180 lb per acre per annum) were compared on 6 long-duration leys. The treatments were repeated for periods of up to 4 years on tiie same swards. The higher N dressing produced 2230 Ib more dry matter per acre than the low rate, an increase of 28",,, and the yield was also more evenly spread throughout the season. There was virtually no clover on the high-N swards. The proportion of clover varied under low N but tended to increase as the season progressed. The sown grasses remained the dominant sward constituents throughout the experiment, and there was no sign of loss of vigour on the high-N swards. Utilized-starch-equivalent outputs were calculated from 3 different swards for 1956-8 and there was a significant positive correlation between the dry-matter yields and utilized-starch-equivalent output of swards.