Perennial Grasses Creating Soil Structure and Raising Fertility

Abstract

Under the conditions of the southwest Ukrainian forest-steppe, planting wind-eroded croplands with mixtures of perennial grasses significantly improves soil structure, stability and fertility. In field trials over the period 2001–2010, the structural coefficient (the proportion of agronomically favourable soil aggregates) depended on the grass mixture, its period of development and the weather. All mixtures under trial proved more effective than natural regeneration. In years with enough rainfall during the growing season, the best soil structure was achieved by a mixture of lucerne and timothy. However, the lucerne succumbed to severe drought whereas bird’s-foot trefoil, which also achieved a good, water-stable structure, proved to be more drought resistant.