Alber, N. B., Brink, G. E. and Jackson, R. D. 2014. Temperate grass response to extent and timing of grazing. Can. J. Plant Sci. 94: 827-833. Considerable differences exist among cool-season grass species in their production potential and response to management variables. We examined the effects of grazing management on forage and root production of two temperate perennial grasses, meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.] and orchardgrass (Dactylis glomerata L.). Grazing factors studied were extent of defoliation (50 or 100% biomass removal) and stage of maturity (vegetative or mature) at grazing. In 2009 and 2010, orchardgrass produced more above-ground biomass than meadow fescue despite yearly precipitation differences. In the drier year (2009), both grasses produced greater above-ground biomass under 100% extent of defoliation at either maturity stage. In 2010, orchardgrass produced greater above-ground biomass when grazed at a mature stage for either extent of defoliation, while few differences existed among grazing treatments imposed on meadow fescue. Grazing treatments had no effect on below-ground growth of orchardgrass either year. Meadow fescue root production was effected in 2010 only; grazing at a mature stage increased below-ground growth for either extent of defoliation. Results suggest that grazing at maturity to remove 100% of biomass maximizes above-ground production of both meadow fescue and orchardgrass, but lengthens the grazing interval and may have a deleterious effect on grass persistence and nutritive value.