1936] MAMMALS OF OREGON 153 



Food habits. In June these squirrels were found feeding on green 

 leaves, tender plant stems, flowers, roots, bulbs, insects, seeds, and 

 young grain. In places the seeds of alfilaria formed over half the con- 

 tents of all the stomachs examined. Seeds of plantain, grasses, and 

 wild mustard were also recognized in the stomachs, also a few cater- 

 pillars, cicadas, and small beetles. In a garden they were eating 

 young cabbage plants, green peas, and young corn. In the fields they 

 were cutting down the growing rye and eating out tender sections of 

 the stems and the flowering heads, cutting many stems for the little 

 food obtained. Later as the grain forms, all of the kernels are eaten, 

 wheat, rye, and barley especially suffering from their depredations. 

 By the middle of harvest time, however, having become excessively 

 fat, they enter a state of hibernation. Apparently they do not lay 

 up any stores of food, and rarely is any food found in their rather 

 small cheek pouches. 



Breeding habits. The females have the usual arrangement of 

 mammae in 5 pairs 1 inguinal, 2 abdominal, and 2 pectoral. The 

 5 to 10 young are born apparently in March and April, and appear 

 out of the burrows in April and May, are well grown by the middle 

 of June, and well fattened by the first of July. In the very mild 

 climate of the Columbia Valley they keep about a month ahead of 

 the higher country ground squirrels. 



Hibernation. During the early part of July most of these little 

 squirrels have accumulated about as much fat as their skins can hold, 

 and they disappear into their burrows to be seen no more until the 

 latter part of February or early March of the following year. When 

 first emerging from their 8 months of inactivity they are said still to 

 be well supplied with fat, which is soon lost during the breeding 

 season, and before food becomes plentiful. Their unusually early 

 hibernation, or aestivation, is probably due to the long, dry summer 

 period and scarcity of moisture. 



Economic status. The great abundance of these little squirrels 

 in an almost exclusively grain-producing area renders them almost as 

 serious a pest as some of the larger species. Over the most populous 

 part of their range in 1896, their numbers were estimated at 50 to 

 100 to an acre and 620 of their burrows were counted on a measured 

 acre. Small fields of grain are sometimes entirely destroyed by them 

 before ripe enough for harvest, and every field within their range 

 suffers to greater or less extent, according to the expense and effort 

 put forth in destroying the squirrels. 



Poisoning, trapping, and shooting are the usual methods of de- 

 struction, but the native enemies of the squirrels should, as far as 

 possible, be protected and encouraged. Of these the badger prob- 

 ably stands first in importance. On 1 acre near Pendleton in 1896 

 62 holes were counted where a badger had dug out the burrows and 

 evidently in most cases had feasted on a fat squirrel at the bottom. 

 Weasels, skunks, bobcats, and coyotes help to keep down, the pest, 

 and numerous hawks and day-hunting owls do their best to protect 

 the crops. 



The squirrels are good eating if the oily fat is removed. 



