THE POTENTIAL VALUE OF BIRDSFOOT TREFOILS (LOTUS SPP.) FOR THE IMPROVEMENT OF NATURAL PASTURES IN SCOTLAND: 1. Common birdsfoot trefoil (l. corniculatus L.)

Twelve introducdons of common birdsfoot trefoil (L. corniculatus L.) obtained from the USA, Canada and the USSR were classified and compared with S100 white and Essex red clovers when grown as spaced single plants and as spaced aggregate clumps on a lowland site at Auchincruive during 1968–69. Semi‐erect and low‐growing forms, early and late‐flowering types were recorded. In terms of DM yield, the Rnssian variety Morshansk and its Canadian descendant Leo were most promising, the former outyielding both clovers over the experimental period. Two sward experiments were conducted at an upland site in south Ayrshire during 1967–8 on the effect of variations of renovation treatment and fertilizer application on the establishment and production of surface‐sown trefoils. The USA variety Empire behaved simflarly to white clover in that it established and yielded satisfactory under all renovation treatments. A marked yield response to K application and a depression caused by fertilizer N were obtained in the second experiment The trefoil varieties Leo and Empire were as productive as S100 white clover. Legume establishment was notably more satisfactory after spring sowing. These results suggest that common birdsfoot trefoil has potential value as an alternative to white clover on dry soils of low fertility in Scotland where grazing pressure is traditionally not very severe.