ANNUAL RYEGRASS FOR DEFERRED GRAZING IN MISSOURI

摘要

Livestock producers in Missouri are interested in annual ryegrass (Lolium multiflorum Lam.) for deferred grazing in winter. Although annual ryegrass is widely used in the southern US for winter pasture, almost no information exists about its use in Missouri. The objective of this .study was to determine the amount of winter forage available from annual ryegrass for deferred grazing in Missouri. Four annual ryegrass cultivars were evaluated in three diverse environments (Linneus, Columbia, and Mt. Vernon) during the winter of 1999-2000. Cereal rye (Secale cereale L.) and wheat (Triticum aestivum L. emend. Thell.) were included as comparisons. Forage from previously uncut plots was harvested in Dec, Jan, Feb, and Mar to determine the stability of yield over winter. Annual ryegrass yields varied from 151 to over 5000 lb/ac, depending on cultivar and location. Generally, yields were greater for Westerwold cultivars than Italian cultivars of annual ryegrass. Yields were highest in the cooler and wetterclimate at Linneus and lowest at Mt. Vemon, where rainfall was 37% below normal during autumn, 1999. At Linneus, but not the other sites, the leaves on all the annual ryegrass cultivars showed signs of freeze damage. Harvesting in Dec, Jan, or Feb had no effect on yield, suggesting that producers could use annual ryegrass successfully for deferred grazing.