ELK GRAZING AND VEGETATION RESPONSES FOLLOWING A LATE-SEASON FIRE IN YELLOWSTONE-NATIONAL-PARK

We studied responses of aboveground production, grazing by elk and the availability of eight elements (Ca, Fe, K, Mg, N, Na, P, Zn) in a Yel lowstone National Park sagebrush grassland following a fire in 1992. W e compared four areas of differing fire history: (1) an area burned in 1992, (2) an area burned in 1992 and 1988, (3) an area burned in 1988 and (4) an area with no recent fire history. The year after burning, graminoids produced more aboveground biomass on burned areas compared with unburned areas. Forages growing on burned soils were highly conce ntrated with all nutrients, except Ca, when elk grazed the site. Despi te nutrient-rich forage on burned areas, elk consumed little forage in these areas. We hypothesized that elk ate less than expected in burne d areas because of a large bloom of lupine (Lupinus sericeus), which m ay be unpalatable to elk.