32 
Colorado Experiment Station 
of these rodents. Frequently they will cut off the roots a few inches 
below the surface of growing alfalfa, thus killing the crop out so 
that it has to be reseeded. 
' These rodents can be destroyed if sufficient effort be made, or 
with less effort they can be so reduced in numbers that injurious 
effects from their activities will be relatively light. Probably poi¬ 
soning is the cheapest means for disposing of them. To be effective, 
the poisoning must be done in the spring before green growth starts, 
as the prairie dogs and kangaroo rats will eat poisoned grain at 
this time, but will not touch it after green things become abundant. 
The State Entomologist and his assistant have worked out success¬ 
ful methods of poisoning these rodents, and will furnish methods of 
making up the poison upon request. Poisoned wheat will be sold 
at practically the cost of preparing it. 
A recently devised method of killing off these small animals is 
by the use of dynamite. When this method is used, a piece of dyna¬ 
mite about an inch long is attached to a fuse long enough to let the 
dynamite well down into the hole. The dynamite is then lowered 
into the hole and earth is securely patted around the fuse so as to 
hold it firmly and stop up the hole at the same time. The fuse is 
then lighted. The dynamite burns without explosion, giving off 
poisonous gases which quite effectually kill any animals in the bur¬ 
row. Most of the dynamite salesmen will supply printed directions 
for this method of exterminating rodents. 
