330 Bulletin 81 



PRAIRIE DOGS 



Prairie dogs are found scattered over large areas within the State, 

 mainly in the northern and in the southern portions. They spread very 

 rapidly. According to record the first prairie dogs found in the Sulphur 



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Fiir. 8. — Which shall havt- the grass — the cattle, which are valuable, or the prairie dogs 

 and har\ester ants, which are of no value? Prairie does and ants destroy grass, roots and tops, 

 and also cause the soil to become washed away by flood waters. Use poisoned grain for the 

 prairie dogs and London Purple for the ants. 



Spring Valley were discovered near Willcox about 40 years ago. Th^y 

 are now infesting at least 200 sections of land in this valley, and ther? are 

 many other sections which have been infested by thsse pests on which the 

 "dogs" have destroyed the grass and have moved away. 



It does not talc? long for prairie dogs to destroy the grass on an area 

 infested by them. They eat the crowns and roots of grasses, and they 

 usually destroy the best pasture grasses first. They also prevent the reseed- 

 ing of the grasses by cutting down the seed stalks, in their efforts to main- 

 tain an open view of their towns. It has been estimated that 20 prairie dogs, 

 with their normal increase, will eat or destroy as much grass in a year as 

 a cow will consume. But this is not all the damage they do, for in destroy- 

 ing the protective grass sod they leave the land bare for erosion, especially on 

 slopes and hillsides. In such districts "washes" will occur which gradually 

 increase in size, until grasses cannot again establish themselves. The writer 

 has observed many such places. In other regions where the erosion is not 

 so great, especially in sandy soil, when the prairie dogs are killed off and 

 the cattle are kept off for one to two years, the good grasses reappear. 



Besides large areas of prairie dog-infested land in the Sulphur Spring 

 Valley, there are many sections of infested grass land in the San Pedro 



