This section is from the book "The Gardener's Monthly And Horticulturist V26", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
I have read your note in the last Monthly on the '* Loco weed," that makes horses crazy, in which you say, " As some half dozen plants go under the suspicion, a splendid chance to tell just what the plant is has been lost." To that I reply, others have not lost the chance.
In the spring of 1882, Dr. Isaac Ott, of Easton, Pa., a skillful investigator of the physiological action of poisons, received from some stock growers in Western Kansas a quantity of one of these Loco weeds and made a series of careful experiments with an infusion of the plant upon various animals, and produced the same effects observed by the cattle men in the West. Its active principle is a powerful poison. The results were published in a i medical journal. Dr. Ott placed specimens in my hands for determination, and I readily identified it as Astragalus mollissimus, Torr. He says, that the same thing has been proved in the case of Sophora sericea, Nutt, and that Oxytropis Lam-berti, Ph., is under suspicion. Cattle and sheep are also said to be affected by these weeds, but in a less degree than horses. They are eaten in early spring before the grasses appear to furnish a more wholesome pasture, and once tasted the animal takes a liking for them. The eating may prove fatal in three or four days, or the victim may linger for a year or more.