Management variabes that affect the yield of forage mixtures during the first year

Abstract

The yield composition of 5 seeding mixtures (grass/legume and chicory) under two defoliation frequencies was studied during the first year. Seeding mixture had a significant effect on herbage DM yield, whereas defoliation frequency did not. Treatments with Avena byzantina and Lolium multiflorum as the grass component yielded
an average 5093kg.ha^-1DM, out yielding those treatments with perennial grasses by more than the double (204%). Despite the absence of a significant effect, all treatments yielded more herbage DM under the more frequent defoliation management. This management involved 60% more cuts than the less frequent management. Sward canopy height, recorded immediately before cutting, was more closely associated to herbage DM yield during spring and had a very low R² during summer. Herbage DM yields were recorded for the cutting horizon, as defined by the difference between sward canopy height and residual height, the latter remaining constant throughout the experimental period. The mean growth rate for the pasture fraction total DM was calculated for each period between two successive cuts, the range lying between 3.9kg.ha^-1.d.^-1DM and 26.0 kg.ha^-1.d.^-1DM. The lowest rates were recorded for the second half of the summer whilst the highest were achieved during spring.