^6 
Colorado Experiment Station 
acquiring the habit when food is scarce, there will be very few locoed 
animals. When first seen eating large quantities of loco weeds, and 
presumably acquiring the habit, an animal should be immediately re¬ 
moved from the herd. Young animals are more apt to acquire the 
habit than older ones. The habit assumes the form of an insatiable 
appetite for loco weeds, and as a result from eating these exclusively, 
the animal suffers from an unbalanced ration and from lack of nour¬ 
ishment. 
Poisonous principle. —The nature of the poison in loco weeds has 
not been determined. It was thought at one time that barium found 
in the plants was responsible, since the symptoms in barium poison¬ 
ing in some respects simulated those of locoism, but this was later 
disproven. 
Preventive measures and treatment. —The most important meas¬ 
ure is to remove the affected animals from loco infested pastures. 
Many letters are received at the Experiment Station asking for a 
cure for locoed animals and in most instances the animals were 
known to still have access to the weeds. A “cure” in a case like this 
is impossible. The afflicted animal should first be taken from the 
infested area, and given a physic (raw linseed oil), and fed well on 
hay and grain of the best quality. Fowler’s solution of arsenic mix¬ 
ed with the grain may be given as an alterative and tonic twice a day. 
The dose for horses and cattle is one-half ounce, and for sheep 
one teaspoonful. This treatment should not be given continuously 
longer than two weeks. If the animal can be placed under the care 
of a competent veterinarian, strychnine and other remedial measures 
may be tried. If not too badly diseased, cattle and sheep, with good 
care and proper treatment, will recover sufficiently to fatten for the 
block. Horses will recover sufficiently, in most cases, to render a 
more or less valuable service, but with few exception they do not be¬ 
come normal and dependable. 
BUCKBEAN (Thermopsis) 
The common buckbean or yellow wild pea in the state is one 
with widely-spreading pods {Thermopsis divaricarpa). It is a tall 
perennial with large leaves divided into 3 leaflets that arise at and 
"a'liate from the end of the leaf-stalk. At the base of the leaf¬ 
stalk, there are two large leaf-like structures, the stipules. The 
flowers are large, pea-like, and yellow. The pods are 3 to 4 inches 
long, 1-4 inch wide, and spread out from the stem. The plant blooms 
in the early spring, forming large, bright yellow patches. It grows 
in rather deep soil along streams, and in diaws. It is distributed 
throughout the state from 5,000 to 11,000 feet altitude. 
The buckbean is regarded with suspicion by some. No authentic 
cases of poisoning from it have come to our attention. 
