Forage Quality of Naturally Restored Legume Species from Burnt Grasslands

Abstract

The aim of the present study is to analyze the chemical composition of legume meadow species participating in post-fire successions in view of their importance for restoring the forage value of grasslands after burning. The object of observation are burnt pasture and meadow grasslands in four locations on the territory of Bulgaria, located in three different floristic regions. The legume species with the highest frequency during the first vegetation period after burning are determined. The content of crude protein, crude fibre, crude fat, ash, nitrogen-free extractive substance, calcium, phosphorus, and nitrogen in the dry forage biomass was measured. Significant differences were found in the values and ratios of the analyzed quality parameters. The Vicia species are characterized by the highest content of crude protein (average 16.35%) in dry matter. The biomass of Medicago falcata is distinguished by the highest concentration of crude fibre, total minerals, calcium and phosphorus, and by a significantly lower content of nitrogen-free extractive substances. The dry matter of Astragalus onobrychis contains the highest amount of crude protein (21.16%) and nitrogen (3.02%), and a low content of crude fibre (26.80%) – an indicator for good quality of the realized forage mass. In contrast, the lowest average values of crude protein (13.61%) and nitrogen (1.94%) are recorded for Trifolium species. The potential of the studied wild legume grasses for restoring the forage value of burnt meadows in relation to specific ecological and geographical conditions is discussed.