Annual ryegrass forage mass distribution as affected by sod-suppression and tillage

Early-season forage mass production of annual ryegrass (Lolium multiflorum Lam.) is reduced in the southeastern USA when ryegrass is established no-till rather than with conventional tillage. Two studies were conducted to evaluate forage mass distribution of annual ryegrass established under tillage vs. no-till. One evaluated the effect of sod-suppression, and the other evaluated past and current tillage practices. In the sod-suppression study, no-till plots established with herbicides produced 27% more forage mass at first harvest than did no-till plots that were mowed. However, tilled plots produced 55% more forage mass at first harvest than no-till plots established with herbicides. After January, no-till plots produced as much or more forage mass than tilled plots in both studies. In the 1994-1995 growing season, forage mass produced at first harvest was positively correlated (P = 0.01) with stand count in both the sod- suppression (r = 0.62) and the tillage history (r = 0.73) studies. After the first harvest, stand count was not correlated (P > 0.11) with forage mass production. In the tillage history study, current seedbed preparation had a much greater impact than past seedbed preparation on early-season production of annual ryegrass. When combined over both studies, ryegrass established with tillage (4.9 tons/acre) and established no-till with herbicides (4.6 tons/acre) produced more season total forage mass than no-till ryegrass established without herbicides (4.3 tons/acre). In annual ryegrass establishment systems, tillage does more than reduce competition from warm-season grasses. However, suppression of warm-season grasses with herbicides is still important for no-till establishment of annual ryegrass.