Yield, persistence, forage nutritive value, and preference of perennial ryegrass under grazing

Perennial ryegrass (PR) is a quality and high yielding forage that tends to lack winter hardiness to persist in the upper Midwest. The objective was to evaluate yield, stand persistence, forage nutritive value, and preference of experimental populations of winter hardy PR grown in monoculture and in mixture with white clover under livestock grazing. Research was conducted in St. Paul and Grand Rapids, MN. Meadow fescue (MF), tall fescue (TF), orchardgrass (OG), a reference PR, and two experimental populations of PR were grazed every 32 days by either horses (St. Paul) or cow-calf pairs (Grand Rapids). Prior to grazing, forage yield and quality samples were collected, and post-grazing, fields were visually assessed for the percentage of forage removal to determine preference. Yields of all PR (6.9 to 7.6 Mg ha(-1)) were similar, but lower compared to other cool-season grasses (CSG). Persistence was similar among all CSG in St. Paul; however, it was lower for all PR in Grand Rapids compared to other CSG. All PR were highly preferred by both horses (>= 74% removal) and cattle (>= 70% removal) and were consistently among the highest for crude protein (CP; 200 g kg(-1)), equine digestible energy (DE; 2.35 Mcal kg(-1)) and bovine metabolizable energy (ME; 2.6 Mcal kg(-1)), moderate for nonstructural carbohydrates (NSC; 136 g kg(-1)), and among the lowest for neutral detergent fiber (NDF; 518 g kg(-1)). Experimental populations of PR produced forage of high nutritive value, but yield and stand persistence may be less compared to other CSG at some locations.