The Relationship between Coverage and Dry Matter Contribution of Forage Legumes in Binary Legume–Grass Mixtures

Abstract

ABSTRACTAn efficient and accurate detection of the contribution of legume dry matter (DM) in legume–grass mixtures is of great importance for a targeted management of legume‐based swards. Legume coverage is a frequently used parameter to describe the dominance structure in vegetation because it is easily accessible. The present study investigates the relationships between legume coverage and different legume species and growth stages. A dataset was generated from a pot experiment that was conducted under controlled conditions across a wide range of legume species (Trifolium repens L., T. pratense L., Medicago sativa L.), proportions of legumes (0–800 g kg−1), and growth stages (tillering to heading). Multiple regression analysis revealed a positive relationship between legume contribution and coverage for the separate legume species (R2 = 0.98–0.99), as well as for the combined dataset including all legumes (R2 = 0.98). Total biomass was related to clover coverage in a complex manner, reducing legume contribution by up to 180 g kg−1 with an increase of total biomass from 300 to 1500 kg DM ha−1 The validation of the models with mixed swards of grass and either white or red clover that were grown in the field showed good results (r2 = 0.98).