STORMS INFLUENCE CATTLE TO GRAZE LARKSPUR - AN OBSERVATION

Livestock producers report cattle deaths from larkspur (Delphinium spp .) poisoning increase during stormy periods. In controlled grazing stu dies, we observed cattle increase larkspur consumption during stormy w eather. Periods of ''gluttonous'' larkspur consumption generally coinc ided with storms during a 1990 grazing study. Cattle consumed larkspur almost exclusively for 20-30 min periods during storms, as opposed to intermittent grazing of larkspur flowers, pods, and leaves. In 1991, weather parameters were measured and correlated with larkspur consumpt ion. Larkspur consumption was negatively correlated with decreasing te mperature and barometric pressure (r = -0.45 and -0.60 respectively); and positively correlated with increasing relative humidity, leaf wetn ess, and precipitation (r = 0.45, 0.74, and 0.27, respectively). Under standing consumption patterns of cattle grazing larkspur will aid in d eveloping management strategies to reduce cattle deaths.