264 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
O. E. McArthur, also of Blunt, S. Dak., states that about fifteen A^ears 
ago his children noticed two or three burrows about a mile from his 
house, and that no particular attention was paid to the inmates, which, 
during the next few years, increased slowly. A little later, however, 
they spread over so much land that their multiplication became a mat- 
ter for serious alarm. At present they occupy a full quarter section 
(160 acres), having surrounded Mr. McArthur's house and taken pos- 
session of all the land near it. 
A cattle ranch in Logan County, Kans., which ten years ago pas- 
tured a thousand head of cattle, will barely support 500 at present, 
owing to the great increase in prairie dog's, which have overrun the 
range. Practicall}^ the whole of the southern half of Logan County 
is now one continuous dog town, estimated to cover about 300 square 
miles. In the past decade the population of this area has decreased, a 
post-office (Elkader) has been abolished, and many homes have been 
vacated, the result, it is said, of the great increase in prairie dogs. 
At Carlsbad, in the Pecos Valley, New Mexico, in September, 1901, 
Vernon Bailey studied a colony of prairie dogs which completely cov- 
ered a 20-acre alfalfa field, 1 or 5 acres in each of two adjoining fields, 
and several acres of prairie. He was told that this large colony had 
spread in three years from a small one in a corner of the alfalfa field. 
E. W. Nelson .states that when he and his brother located ranches 
in a mountain valley in eastern Arizona in 1881, the only prairie dogs 
in the vicinity were a colony 3 miles distant, inaccessible except by 
way of a narrow box canyon. About three years later a prairie dog's 
burrow was found on the ranch, after which the animals multiplied 
steadil3% until in 1895 they occupied a large part of the valley. 
Complaints are constantly received of the spread of the pests on farm 
lands adjoining Government, railroad, school, and other lands, over 
which the inhabitants have no jurisdiction. This is a very serious 
evil, and one with which it is exceedingh^ difficult to cope. 
FOOD. 
The normal food of the prairie dog is grass, chiefly the bunch grass 
of the plains. In addition to this, grass roots, other plants, seeds, and 
sometimes insects are eaten. 
DESTRUCTIVENESS. 
The damage done by prairie dogs consists in the loss of grass and 
other crops eaten, or buried under the mounds; in the accidental 
drainage of irrigation ditches,^ and in the danger to stock from stum- 
^In Stillwater Valk'v, ^Montana, an irritrating ditch on a side hill was tapped by a 
prairie dog burrow and the water came out 50 feet lower down on the slope. The 
hole was twice stopi)ed and the ditch moved a little, but the break recurred, and it 
was finally necessary to dig a new ditch around the washout. 
