LUCERNE-GRASS SWARDS WITH DIFFERENT NITROGEN APPLICATION AND GRASS COMPONENTS .1. YIELD OF DRY-MATTER

Results on DM harvested from two series of experiments with mixtures of lucerne [Medicago sativa] and timothy [Phleum pratense] or smooth brome grass [Bromus inermis] (Series I, 22 harvest years) and mixtures of lucerne and meadow fescue [Festuca pratensis] or cocksfoot [Dactylis glomerata] (Series II, 10 harvest years) are presented. The experiments were sown as replacement series with pure stands of all species and three mixtures of different proportions of each lucerne-grass pair. Three levels of applied N were imposed: 0, 100 and 200 kg/ha N, respectively. The experiments were cut three times a year. P and K were applied each spring. Herbage dry-matter yield and botanical composition were determined. As a result of the experiments, meadow fescue and cocksfoot are recommended for inclusion in mixted lucerne-grass swards. About 15 kg/ha lucerne and up to 10 kg/ha of meadow fescue or 5 kg/ha of cocksfoot, respectively, are the recommended sowing rates. N application is of little value in these mixed swards as the dry matter return is less than 14 kg per kg N applied.