P, 
rad 
STOCK-POISONING PLANTS OF THE RANGE. 21 
PREVENTION OF LOSSES. 
In Farmers’ Bulletins 536 and 720 attention was directed to the 
fact that most of the losses from poisonous plants occur at times 
when the animals are short of feed, and it was suggested that the 
larger part of the stock poisoning is indirectly due to scarcity of 
proper forage. ‘This fact of the intimate relation of scarcity of feed 
to stock poisoning can not be too strongly impressed upon the people 
who handle range animals in the West. 
There is apparently a popular idea that range animals will volun- 
tarily seek out poisonous plants and eat them by preference. It 
may be stated as a general fact that this is not true. Animals 
seldom eat poisonous plants except as they are driven to do so by 
lack of other food. Almost all poisonous plants are actually dis- 
tasteful to live stock and under ordinary circumstances will be 
avoided. ‘The only exception to this, perhaps, is the group of loco 
plants. Animals do frequently acquire a taste for loco and under 
some circumstances will eat nothing else, even in the presence of 
other forage; and yet the initial feeding in the case of loco plants 
is almost invariably brought about by scarcity of food. 
It has long been known that loco eating is ordinarily commenced 
in the winter season or in the early spring when the loco plants are 
green and luscious, and before the grass has started. The loco plants 
at that time are the most prominent plants on the plains, and 
animals commence to eat them because of lack of other food. Many 
animals after feeding upon loco a short time acquire a liking for it 
and will continue to eat it even in the presence of an abundance of 
other food. This is not true, however, even of all loco-eating ani- 
ymals, for there are very many which, after the grass has started, 
will leave the loco and will recover entirely from the effects which 
have been produced by the preceding feeding. 
In the matter of the other plants, the relation between starvation 
and the eating of the poisonous plant is still more marked. Tor 
instance, the larkspurs spring up immediately after the snow leaves 
the mountains and grow much more rapidly than the surrounding 
grasses, and if cattle are allowed to go up to the upper ranges before 
the grasses have had a fair start, they find already occupying the 
ground the succulent larkspur plants in huge numbers. Sometimes 
the cattle come from dry winter feed and are anxious to gorge them- 
selves with any green material they find. Under such circum- 
stances if they come upon a field of larkspur they frequently eat 
enough to produce fatal consequences. Later in the season there is 
very much less danger from larkspur because of the abundance of 
other food. If, however, cattle are driven from one range to 
another and the trail passes through a mass of tall larkspur, it is not 
