On some of the Indian reservations of the Southwest, the condition has been pitiful. On the Navajo Reservation, in particular, the Indians have carried on a losing fight against drought and rodents. It has often been necessary for them to replant their corn three and four times a season, since kangaroo rats and other native rodents dig up the kernels as rapidly as they are planted. Prior to the spring of 1936, there had been four years of drought, and this, coupled with rodent damage, had reduced corn production to the point where the Indians had barely enough for the spring seeding. All were clamoring for aid, and in order to save their last crop of corn it was necessary to detail a foreman with four or five E.C.W. Indians to go from farm to farm and conduct rodent-control operations.
Forest and Forage Protection
The Forest Service is endeavoring to carry on a reforestation program throughout much of the cut-over area in the Lake States and the Pacific Northwest. One of the chief problems to successful reforestation is the control of rodents, particularly the snowshoe hare. In the Olympic Forest in Washington, the snowshoe hare has destroyed as much as 40 percent and damaged 70 percent of the Douglas fir seedlings. In Michigan and Wisconsin, it was necessary to carry on extensive rodent-control operations to permit the seedlings to survive. Much of this work would never have been possible but for E.C.W. help.
In the open area, jack rabbits have become a serious pest. The Biological Survey, in 1934, received a petition bearing the signatures of more than 8,000 individuals of eastern Colorado, requesting Government aid in killing jack rabbits, which were ravaging the meager stocks of forage left after drought and wind had taken their toll.
The Forest Service recognized that rodent control would be essential if the Plains Shelterbelt program of planting trees from the Canadian border to Texas was to be effective, and in 1935 approximately one-tenth of its entire appropriation for the program was expended for rodent control under the supervision of the Biological Survey. Crews patrolled the planted areas constantly to prevent the gnawing of the seedlings by jack rabbits and pocket gophers.
Aid in Erosion Control
The permanent benefits accruing from the E.C.W. rodent-control program have been enormous from the standpoint of erosion control alone. An associate range examiner of the Forest Service has the following to say regarding the effect of rodents on erosion in the Boise watershed of Idaho:
"Rodents, numerous and spreading over nearly 80 percent of the Boise watershed, have undoubtedly been responsible for no small part of the present erosion. Wholly dependent upon the herbaceous plants for their food supply, their tremendous numbers, along with over-grazing by livestock and unfavorable climate, have been an important contributing factor in depleting this cover, and thus have greatly reduced the protection afforded the soil and subjected it the more to increased sheet erosion. Even light rains on rodent-infested areas are likely to start cutting, which may develop into destructive gully erosion because of the almost immediate accumulation of run-offs in the myriads of burrows and channels which these animals construct just under the surface of the soil."
The control of rodents is vital to the successful operation of reclamation projects in the western third of the United States. Rodents, particularly pocket gophers, find the banks of irrigation canals an ideal location for their burrows and runways. These subterranean passageways frequently are the cause of serious breaks in canals, through which the flow of irrigation water is diverted and wasted to flood adjacent lands, destroying valuable crops, and indirectly ruining others by causing delays in delivery of water. Through the E.C.W. program, C.C.C. crews working under the direction of experienced foremen trained by the Biological Survey have greatly reduced this menace. In the past year alone half a million acres of canal banks and contiguous lands were treated by C.C.C. rodent-control crews with a thoroughness that will be of lasting benefit to the nation's reclamation projects.