Response to Soil Moisture Supply in Three Leguminous Species

SUMMARY Soil moisture is an important factor in the distribution of Trifolium repens, Lotus corniculatus and Medicago lupulina. The first proved to be the most successful on moist soil, growing vigorously and forming numerous seeds. However, the plant was unable to avoid desiccation in droughted conditions where physiological processes such as root and shoot growth, and seed production were inhibited. In moist and dry soil, the seed production and vegetative yield of Lotus corniculatus were consistent. However, the slow‐growing seedlings and adult plants were relatively intolerant of severe drought. The annual, Medicago lupulina , displayed the greatest plasticity. On moist soils it formed substantial vegetative parts and prodigious numbers of seeds. In doughted conditions this species was the most tolerant of the three legumes at all stages of the life history, forming many seeds even when the vegetative yield was relatively low.