Date and plant community effects on elk sedge forage quality

Abstract

Elk sedge (Carex geyeri Boott) is one of the most important livestock and big game forages in many areas of the western U.S. It is one of the most prominent forage species in the diets of cattle and elk utilizing forested rangelands. Despite its acknowledged ecological and economical importance, very little is known about the factors influencing the forage quality of elk sedge. Effects of sampling date, plant community, and their interaction on the neutral detergent fiber, acid detergent fiber, and crude protein levels of elk sedge are reported for samples collected at the Starkey Experimental Forest and Range and the Bridge Creek Wildlife Management Area, both in northeastern Oregon, during January, April, July, and October of 1997 and 1998. Neutral detergent fiber levels in elk sedge were lowest in mid-October (average = 71.3%) and highest in mid-July (average = 76.1%). Acid detergent fiber was lowest in elk sedge collected in mid-October (average = 37.3%) and highest in mid-July (average = 39.0%) and mid-January (average = 39.2%). Elk sedge from the Douglas-fir/ninebark community was lowest in acid detergent fiber (average= 38.1%). Crude protein was highest (average = 8.0%) in mid-July elk sedge samples and lowest (average = 5.7%) in mid-January samples. Elk sedge from the ponderosa pine/fescue community was lowest in crude protein (average = 5.9%). All forage quality parameters exhibited variability between years. Although sampling date and plant community effects were detected, the forage quality of elk sedge appeared relatively stable compared to other native forages. A more intensive spring sampling campaign is needed to characterize the relationship between elk sedge phenology and forage quality dynamics.