Tall-growing grasses, including orchardgrass, smooth bromegrass, meadow fescue and timothy, maintain productivity and persistence when a 3-4” residue is left. That’s according to Geoff Brink, USDA-ARS research agronomist at the U.S. Dairy Forage Research Center, Madison, WI.
He studied the effects of the extent and timing of grazing at various heights. Permitting grasses to fully mature to mob-graze reduces grass productivity, quality and tiller density compared to vegetative grazing, and leaving a 12” residue doesn’t improve grass productivity.
But grazing grasses when 6” tall or less in early spring or during summer drought will reduce annual productivity compared to grazing at 12”. The reduction will depend on the severity of stress that follows.