Stoloniferous red clover cv. Rubitas is a valuable companion to PRG and phalaris

In established pasture swards, legumes contribute and transfer nutrients to non-legume species, but are thought to contribute and transfer little during the establishment phase. The nutrient contribution of stoloniferous red clover Trifolium pratense cv. Rubitas during the pasture establishment phase may have been underestimated. To test this hypothesis a pot study was sown in April 2014. Perennial ryegrass Lolium perenne (PRG) cv. Reward was sown alone at 25kg/ha or in combination at two sowing rates, 12 and 20kg/ha with Rubitas at 5kg/ha. Phalaris (Phalaris aquatica) cv. Advanced AT was sown alone at 5kg/ha or with 3kg/ha Rubitas. Rubitas was also sown alone at 6kg/ha. After establishing for 75 days, plants were exposed to defoliation intervals of 10, 20 and 40 days defoliated 8, 4 and 2 times, respectively. These defoliation interval treatments were combined with three residual heights of 25, 50 and 100 mm. Material harvested was hand separated into species, weighed and dried. Results for all treatments and means showed a significant (P<0.0001) effect of species, defoliation interval, species by defoliation interval and residual height by defoliation interval. For treatments that included Rubitas, there was a significant (P<0.0001) increase in DW yield of the companion grass when compared to the PRG or phalaris sown alone. The inclusion of Rubitas increased the combined DW yield of PRG and phalaris by 72% and 179% respectively compared to PRG or phalaris sown alone. Rubitas nutrient contribution and transfer may affect regrowth recovery after defoliation. Further work will seek to quantify Rubitas establishment mechanisms and enhance management for economic and environmental gains.