Seeding ratios and rates that maximize annual forage production in Black soil zones of central Saskatchewan

Abstract

Three different seeding densities and four seeding ratios of spring and fall crop components for annual forage production were evaluated for maximizing silage and fall regrowth yield in a 3-yr study at Melfort, Saskatchewan. Binary mixtures of a spring cereal, barley (Hordeum vulgare L.) or oat (Avena sativa L.), and a fall crop, fall rye (Secale cereale L.) or Italian ryegrass (Lolium multiflorum Lam.), were seeded at three total stand seed densities (150, 275 and 400 seeds m-2), which consequently resulted in the following spring:fall seeding crop component ratios: 1:0, 2:1, 1:2 and 0:1. Both spring and fall crops were harvested when the spring cereals were at the soft-dough stage (silage cut) and late in the autumn (fall regrowth cut). Average spring crop component yield was greater for the silage cut (4806 kg ha-1) than for the fall regrowth cut (329 kg ha-1), and total sward yield was greater for the silage cut (5995 kg ha-1) than for the fall regrowth cut (1261 kg ha-1). Productivity of the fall component was 1173 and 929 kg ha-1 for the silage and fall regrowth cuts, respectively. Total crop yield was often maximized with seeding ratios of 60% spring:fall crop component or greater for the different combinations. Fall regrowth cut yields were always maximized by seeding 100% fall crop component. The spring crop component yield, especially for the oat mixtures, contributed very little to fall regrowth yields. Stand seeding rate frequently affected spring component and total crop yield, but not fall crop yield. Silage and annual yield for the spring crop and total sward increased with increase in stand seeding rate. Fall crop yield was not affected by stand seeding rate or its effect was of questionable practical importance. Italian ryegrass produced the most fall regrowth yield. Weed management was identified as a possible area for future research with regard to seeding ratios and rates for annual forage stands. Key words: Monocrop, intercrop, annual forage, seeding rates, seeding ratio