Assessing eight grass species for pasture by measuring etiolated spring regrowth

Abstract

Grazing by herbivores can affect root carbohydrate reserves of grass species. A grazing study was conducted on an irrigated pasture near Outlook, Saskatchewan, Canada, during the summers of 1991 and 1992 t o determine etiolated regrowth after grazing of reed canarygrass ( Phalaris arundinacea L.), slender wheatgrass ( Elymus trachycaulus (Link) Gould ex Shinners subsp . trachycaulus), intermediate wheatgrass [ Thinopyrum intermedium (Host) Barkw. & D.R. Dewey subsp . intermedium], orchardgrass ( Dactylis glomerata L.), meadow bromegrass ( Bromus biebersteinii Roem. & Schult.), smooth bromegrass ( Bromus inermis Leyss.), tall fescue [ Festuca arundinacea (Schreb.) Wimm.] and timothy ( Phleum pratense L.) in order to eva luate the suitability of these species for grazing. All eight species were mob-grazed by sheep at a stocking rate of 30 animals ha-1. Carbohydrate reserves were estimated by determination of etiolated regrowth. Meadow bromegrass produced the greatest etiol ated regrowth and timothy the least. Based on production of etiolated regrowth the grasses were ranked into three groups - meadow bromegrass and intermediate wheatgrass ranked highest, smooth bromegrass, reed canarygrass, slender wheatgrass and orchardgra ss ranked intermediate and timothy and tall fescue ranked lowest. Key words: