THE EFFECTIVENESS OF THE USE OF PERENNIAL GRASSES IN SOLVING THE PROBLEM OF BIOLOGIZATION OF AGRICULTURE IN THE REPUBLIC OF KARELIA

Abstract

One of approaches to biologization of agriculture in Karelia is a widespread use of perennial grasses, which are a source of fodder and perform important ecological functions. We compared yield and protein productivity (tons/hectare) of one- and three-species grass stands including foxtail clover Trifolium rubens, eastern galega Galega orientalis, alfalfa Medicago varia Mart, smooth bromegrass Bromus inermis, and timothy Phleum pratense grown without mineral fertilizers or with N45P60K90 using the two-cut mode of mowing the green mass. Clover (dry weight up to 8.6, crude protein 1.51), as well as alfalfa + clover + timothy (9.4 and 1.32, respectively) featured the highest productivity. The annual spring application of mineral fertilizers caused but an insignificant increase in the yield of clover biomass, which suggests that there is no need for their application. For the biologization of a northern agriculture, it is recommended to cultivate (for two to three years) a pure grass stand of red clover, as well as a three-species stand including clover, alfalfa and timothy (six to seven years). In а pasture, legume-cereal perennial grass stands accumulate in the soil up to 9.0 ton/hectare of mowing root residues, total nitrogen content being up to 113.0 kg/ha over a five-year period, thus contributing to a slight increase in humus content and a decrease in soil acidity.