Overseeding Alfalfa with Rye and/or Annual Ryegrass by Broadcasting or Drilling.

A forage system based on alfalfa (Medicago sativa L.) that provides winter productivity without sacrificing summer or autumn forage production could be beneficial to the dairy, beef, and equine industries in the southeastern USA. The objectives of this research were to characterize the effect of drilling or broadcasting rye, annual ryegrass, or a combination of the two into existing stands of alfalfa. A small plot trial was conducted over three years on mature alfalfa stands at the University of Georgia's Plant Sciences Farm located near Watkinsville, GA. Treatments consisted of combinations of either a broadcast or drilled planting method and overseeding with rye (Secale cereale L.; RYE), annual ryegrass (Lolium multiflorum Lam.; ARG), or a combination of rye and annual ryegrass (RARG) and an untreated control arranged in a randomized complete block design (four replications). Over the three years, the total forage yield of the forage system was increased (P < 0.001) by 2700 lbs DM/acre (34%) by overseeding with RYE or RARG and by 1400 lbs DM/acre (16%) when overseeded with ARG, compared to the control. Planting method did not have a consistent effect (P > 0.10). Overseeding did reduce the contribution of alfalfa to total yield in the April and May harvests relative to the control (163 vs. 896 lbs DM/acre and (1676 vs. 2317 lbs DM/acre). However, there were no effects of overseeding species or planting method on summer and autumn alfalfa yields nor on stem count in any of the three years. Alfalfa can be overseeded with rye and/or annual ryegrass by drilling or broadcasting to increase total yield without reducing alfalfa production during the summer or autumn or hastening stand decline.