File:Control of field rodents on California farms (1965) (20692107185).jpg

If placed where squirrels are accustomed<brto feed and play they will soon discover<brthe grain and commence feeding.
Anticoagulants are no hazard to chick-
ens or turkeys, but dogs and cats will be
killed if they feed for several days on the
bait or if they repeatedly eat rats killed
by the poison. In some situations it may
be desirable to surround the bait box with
a wire fence of large mesh (hog wire)
that will admit squirrels but exclude
larger animals and children.
There is little danger to human begins
from anticoagulants. If a child or adult
eats some prepared bait he should be
caused to vomit and a physician called
at once. Treatment includes transfusion
with whole blood of appropriate type and
giving Vitamin K by mouth or intraven- ously.

Carbon disulfide gas. Ground squir-
rels and some other rodents can be con-
trolled with poisonous gases. Gases will
also kill other animals living in squir-

rel burrows, such as skunks, cottontails,
burrowing owls, and snakes. The chemi-
cals which have been used include carbon
disulfide (CS₂; often called "carbon"),
carbon monoxide (CO), sulfur dioxide
(SO₂), methyl bromide (CH₃Br), hydro-
cyanic acid (HCN), chloropicrin (CCl₃-
N0₂) and tetrachloroethane (C₂H₂Cl₄).
Carbon disulfide is the gas most widely
used for ground-squirrel control. This
liquid chemical takes fire and burns
readily; it evaporates easily and quickly;
and, in the vapor or gas state, it is highly
explosive. Stocks of carbon disulfide
should be tightly stoppered to prevent
loss and should be stored out of doors in
a cool, shady place free from fire, sparks,
or exposed lights. The fluid corrodes tin
cans readily. Carbon disulfide is poison-
ous to man and to most animals, but it
does not readily kill fleas.
Since it is heavier than air, carbon
disulfide will settle in the lowest parts of
an underground burrow, and will not