Pasture renovation and grazing management impacts on cool-season grass pastures

Legumes have been shown to increase production in cool-season grass pasture s. However, they are included he relatively few acres of pasture. A split p lot experiment with six replications was conducted to evaluate the impact o f pasture renovation and grazing management on forage production and specie s composition of cool-season grass pastures. Grazing management main plots were grazed to leave low (2-4 in.), medium (4-6 in.), or high (6-8 in.) res idue levels, Main plots were intensively grazed (50 000-70 000 lb of cows p er acre) five or six times per grazing season by lactating Holstein cows, S ubplot pasture renovation treatments were (i) an untreated check, or spraye d with glyphosate and interseeded with (ii) alfalfa (Medicago sativa L.) (i ii) red clover (Trifolium pratense L.) and birdsfoot trefoil (Lotus cornicu latus L.), or (iv) "graziers mix" (a mixture of legumes and grasses), Areas that were grazed to leave low residue level produced less forage mass (4.7 ton/acre) than areas grazed to medium (5.4 ton/acre) or high (5.5 ton/acre ) residue levels. When averaged across years and grazing management treatme nts, renovated areas produced 1.8 ton/acre (46%) more forage than the contr ol, Of interseeded species, alfalfa, red clover, and orchardgrass persisted through the study (more theta 25% of the dry matter in st least one of the pasture renovation treatments). By June 1998, thistle (Carduus and Cirsium spp.) was present in all treatments. Fewer thistle was present in areas th at were grazed to leave low residue (10 sq yd) than high residue (18 sq yd) and in renovated areas (9 sq yd) than the control (22 sq yd). The addition al forage produced as a result of pasture renovation cost from $8.07/ton to $12.81/ton. This study indicates that pasture renovation can be a valuable tool for increasing forage production in cool-season grass pastures.