425 



B 20730; B20T2 9 



Destructive Activity of Prairie Do^s on Cultivated Crops. 



At left, field of oats, showing normal production at harvest time ; at right, a 

 contrasting view of a portion of the same field invaded by prairie dogs. Where 

 the prairie dogs have attacked the crop, nothing is left to harvest. Corn, 

 wheat, oats, rye, barley, feterita, and alfalfa are among the valuable grain and 

 hay crops of the United States which prairie dogs, ground squirrels, pocket 

 gophers, jack rabbits, and similar rodent pests destroy to the extent of 

 $150,000,000 annually. 



As long as stockmen could merely move on to fresh pas- 

 tures with their flocks and herds and there was abundance 

 for all comers, there was little concern over the great 

 stretches of fertile range lands denuded and made unpro- 

 ductive by the hosts of rodents feeding undisturbed upon 

 them. With increasing settlement of the country, larger 

 numbers of live stock, keener competition for the more pro- 

 ductive ranges, and reduced areas of free Government 

 pasture lands, stockmen began to cast about for means of 

 maintaining their live-stock production. When it became 

 apparent that the carrying capacity of their pasture ranges 



