Conditions of poisoning Larkspurs are among the early spring plants, blossoming in late April and May. Animals turned out to graze in woods in the spring may eat the plant, especially if other herbage is scant. Cattle are the animals most often poisoned.
Horses are susceptible to the poisoning but generally avoid larkspurs.
Sheep, although seemingly resistant, can be poisoned by large amounts. Fatal poisoning of an animal may result from a single day's consumption of 1 percent or less of the animal's body weight of larkspur plants.