Establishment Clipping of Tall Fescue and Companion Annual Ryegrass

AbstractDue to its soil stabilizing ability, annual ryegrass (Lolium multiflorum Lam.) is sometimes used as a companion crop with tall fescue (Festuca arundinacea Schreb.). Problems arise, however, because of the competitive nature of annual ryegrass. The purpose of this study was to develop a clipping treatment that could be used during turf establishment to allow annual ryegrass to effectively stabilize the soil in a mixture with tall fescue but would result in a small amount of annual ryegrass in the mature stand. Three field studies were conducted over a 3‐yr period on Kirkland silt loam (fine, mixed, thermic, Udertic Paleustoll) in central Oklahoma. In the first study, individual seedlings were clipped in a factorial arrangement of cutting heights, weeks from emergence to first clip, and clipping repetitions. Regression indicated that 22 to 50% of the variability in shoot and root growth at 60 d of age could be attributed to initial clipping treatments. In a second study, on the first day of emergence 90% of ryegrass seedlings had emerged versus 50% of the tall fescue seedlings, suggesting the potential for managing species dominance via clipping. A third study evaluated two seeding rates and seven clipping treatments (developed in the earlier experiments) on 4:l fescue/ryegrass mixture. Waiting 6 wk before initially cutting the turf favored annual ryegrass, whereas tall fescue was generally favored by a single, close clipping (0‐7 mm height) shortly after annual ryegrass emergence (0‐3 d after emergence). Initial clipping treatments reduced ryegrass ground coverage at 60 d from 82% to as little as 46%.