Species composition determines forage quality and medicinal value of high diversity grasslands in lowland England

Current intensified livestock production threatens global biodiversity and food security. Increasing the use of semi-natural, species-rich grasslands for grazing and hay-making could serve as a way to bridge biodiversity conservation and livestock production but we know little about the nutritional composition of native grasslands. To determine the effect of grassland biodiversity on forage quality and the potential benefits and limitations of using conservation grasslands for agriculture, I conducted ecological and ethnobotanical research at 30 grassland sites in Oxfordshire, England. Species-richness and composition increased forage dry matter, sugar, and Phosphorus (P) content. Forage from species-rich grasslands contained up to 27% more protein, 56% more Phosphorus (P), 106% more Potassium (K), and 183% more Calcium (Ca) than cereals and conventional hay and met the nutritional requirements of beef cattle, sheep, and horses. Farmers and graziers valued species-rich grasslands were (1) the medicinal effect of specific grassland plants on livestock, (2) affordability, (3) the resilience of species-rich grasslands to drought and flooding, (4) conservation, and (5) marketability of pastoral products. The main factors inhibiting the (continued or increased) agricultural use of species-rich grasslands were restrictions on time of grazing, restrictions on time of hay-cut, and reduced grassland yield and forage quality due to recent increases in invasive plants. More flexible agro-environmental guidelines around species-rich grassland use are necessary to balance the agricultural as well as ecological value of these landscapes