52 
BULLETIX 475^ U. S. DEPAETMEXT OF AGEICULTTJBE. 
(ground together in a mortar ) over about 4 quarts of tlie dampened baits, 
stirring to distribute the poison evenly. 
The runways, which are usually from 4: to 8 inches beneath the 
surface, can be located by means of a probe made of any strong 
handle an inch in diameter and 36 inches long. One end should be 
bluntly i^ointed. Into the other should be fitted a piece of three- 
eighths-inch iron rod, protruding about 12 inches, and bluntly 
l^ointed. A foot rest aids in probing hard soils. By forcing down 
this iron rod near gopher workings, or a foot or two back of fresh 
mounds, the open tunnel can be felt as the point breaks into it. The 
blunt end of the instrument is now carefully used to enlarge the hole, 
a bait or two is dropped into the run, and the probe hole closed. 
One soon becomes exj)ert in locating the runs, and a man can treat 
from 300 to 500 gopher workings in a day. Baits need be placed at 
only two points in each separate system or group of from 10 to 30 
mounds, which is usually the home of a single gopher. Baits placed 
in open underground runs have invariably killed the gophers, and 
the method has found great favor wherever it has been introduced. 
At the Converse Xursery, in California, wood rats or ** pack *' rats 
{Xeotoma) have been found responsible for a considerable part of 
the damage to transplants usually ascribed to rabbits. 
Wood rats eat little or nothing of the trees they cut, but carry the 
green tips into their nests to store away, as they do many other 
things for which they apparently have no real use. These animals 
are rarely killed by any of the baits which have been described, 
though they pack away such baits readily enough. Elective results 
Avere obtained by dusting baits liberally with finely powdered strych- 
nine, as the rats were killed in packing them. Dry oatmeal biscuits 
one-half inch square and one-fourth inch thick, cut from a stiff 
dough of oatmeal and water after rolling it in sheets, proved to be 
especially successful baits. Eaisins and whole corn may also be used. 
Though both cottontails and jack rabbits fall victims to poisoned 
oats during periods when their natural food is scarce, this poison can 
not always be relied upon to destroy them when it is most important 
to check their depredations. Green or ripening grain heads of barley 
or wheat are among the most attractive baits in summer. Soaked 
for 48 hours or more in a solution of 1 ounce of strychnine sulphate 
and one-eighth ounce of saccharine in 2 gallons of water, such baits 
have occasionally proved very successful. They should be used only 
in locations where live stock is not endangered. 
Investigations on the Pike National Forest by Forest Expert H. S. 
Reinsch have developed the fact that on that Forest hulled oats is the 
grain most relished by mice and hulled barley is the most desirable 
grain for poisoning all species of rodents. On the Arapaho National 
Forest groats is considered superior to wheat for use in poisoning. 
