There are at least 100 species of Lupine (Lupinus sp.) in the Pacific Northwest. Their habitat ranges from coastal plains to sub alpine regions of the interior. The most distinguishing characteristics of the plant are its deeply palmate lobed leaves and its often bluish/purple showy, often white-tipped flowers. There is one species growing in northeastern Oregon, Sulphur lupine (Lupinus sulphureous) that has creamy to yellow flowers. Lupine, like alfalfa and clovers, is a perennial legume that fixes nitrogen in the soil. Mature plants have hairy dark colored seedpods.
Lupine is a concern to many livestock owners in Grant County, and there have been incidents, which have caused severe damage to grazing cattle. Grazing cows that ingest Lupine during early pregnancy (first 40-70 days) may have deformed calves at birth. This condition is called "crooked calf disease" as calves are born with twisted or crooked legs. Avoiding grazing cows in areas that have high concentration of Lupine with little other forage available can be good management. There has been a Lupine developed that is not toxic. It is planted on roadside rights-of-way to prevent soil erosion.
The alkaloid poisons in Lupine are the greatest threat to sheep. A lethal dose of seeds and pods is 1.5 percent of the body weight. The pre-flowered plants provide good forage for sheep. Lupine does not cause birth defects in sheep.
Goats are much more tolerant to Lupine than other animals and toxins have been detected in milk from lactating goats. In 1981 in Northern California a boy was born with deformed hands and arms. The mother had consumed goat milk during her pregnancy. Also puppies and goat kids were born with deformities. The primary forage for the goat was lupine. It was not possible to prove that the milk from the goat was the culprit; however, there was strong circumstantial evidence to support it. The parents originally blamed the problem on herbicides applied on the local forest.
Lupine is found throughout Grant County, mainly in the uplands and forested areas. There have been instances in Grant County where Lupine has been a problem causing crooked calf disease. Cattle do not prefer lupine as forage, and problems usually occur in drought conditions or overgrazed situations where there is little else to eat. Tordon, Escort, or 2,4,D ester formulations reportedly control Lupine.
Dick Field is coordinator of the Grant Weed Control. He can be contacted at 575-1554.