Energy potential of reed canary grass as an energy crop in organic agriculture in Lithuania

Abstract

The present paper provides the results on the energy potential of the swards composed of pure reed canary grass (Phalaris arundinacea L.) and its mixtures with legumes (Galega orientalis, Lupinus polyphyllus, Melilotus officinalis) grown for biogas production. The experimental evidence suggests that sward species composition and timing of the 1st cut exerted some effect on biomass yield. All swards, irrespective of the species composition, were higher yielding in the 1st cut, especially when it was taken in July. The total annual dry matter (DM) yield of two cuts for more productive swards exceeded 9 t ha-1. The highest biogas yield from the biomass of perennial grasses was produced from the second cut. The results show a large variation in the potential for bio-energy (biogas) of different swards, ranging from 52 to 138 GJ ha-1. The two swards, mixture of reed canary grass with goat's rue and pure reed canary grass, had the greatest energy potential -138 and 130 GJ ha-1, respectively. In all cases organically grown mixtures had an important advantage over pure swards applied with nitrogen.