COMPONENT YIELDS AND QUALITY OF BINARY-MIXTURES OF LUCERNE AND PERENNIAL, ITALIAN OR SHORT-ROTATION HYBRID RYEGRASS

Studies were conducted to characterize sward dynamics of lucerne (Medi cago sativa L.) and perennial, Italian or short rotation hybrid ryegra ss (Lolium perenne L. and L. multiflorum Lam.) binary mixtures under h ay management. Lucerne/timothy (Phleum pratense L.) mixtures were incl uded as controls. The study was conducted on two farms in central Penn sylvania, USA on Hagerstown silt loams (fine, mixed, mesic hapludalf). Total dry matter yield, grass yield and yield of digestible dry matte r were higher for tetraploid perennial and tetraploid Italian ryegrass mixtures than for timothy mixtures. Seasonal production differed for the three kinds of ryegrass. Italian ryegrass dry matter yields were h igher in cuts 2 and 3 than perennial ryegrass yields. Grass yields rep resented 34%, 24% and 12% of total yields of the Italian, perennial or short rotation, and timothy mixtures, respectively. However, herbage in vitro dry matter digestibility of Italian was lower than that of pe rennial ryegrass. The tetraploid perennial ryegrasses Grimalda and Rev eille had high-ranking N concentrations more frequently than other cul tivars, while Barvestra and Reveille tetraploid perennials and Bison s hort rotation ryegrass had high-ranking dry matter digestibility value s more frequently than the other cultivars. Perennial ryegrass cultiva rs and Lipo tetraploid Italian ryegrass persisted well for 4 years and produced higher yields with a lower weed content than timothy mixture s. It is concluded that perennial ryegrasses and Lipo Italian ryegrass should be recommended over timothy, as companion grasses with lucerne .