430 Yearbook of the Department of Agriculture, 1920. 



dual college. The operations included demonstration of the 

 most effective methods of destroying these pests in farming 

 communities and the organization of systematic township 

 and county campaigns. These animals were reported as 

 causing crop losses aggregating from six to nine million dol- 

 lars annually in the State. In this campaign the then enor- 

 mous quantity of five-eighths of a ton of strychnine was 

 used. This was prepared and applied to grain bait under 

 supervision of Department of Agriculture and State experts 

 according to methods determined through extended field ex- 

 periments previously conducted by the Biological Survey 

 and the State experiment station. 



This work, organized in seven counties, was the beginning 

 of systematic cooperative campaigns to clear of rodent pests 

 great areas, involving Federal, State, and private lands, in 

 which the costs were paid by the respective owners. The 

 organized movement has gone forward with remarkably 

 rapid strides because it has met a very important need in a 

 practical, effective, and economical way. 



These campaigns demonstrated that losses from rodent 

 pests not only constitute an entirely unnecessary drain upon 

 the productive capacity of the farms and stock ranges, but 

 that they may be permanently eliminated at a cost which is 

 but a small fraction of the damage occasioned during a single 

 year. Where the expense for labor and poisoned materials is 

 included, the cost of this work usually ranges between 4 and 

 10 cents an acre, depending on the kinds of animals and their 

 abundance. Where the farmers and stockmen utilize the 

 services of their regular farm and ranch help in distributing 

 the poisoned grain on their land no increased cost of opera- 

 tion is involved except the cash outlay for poison supplies, 

 which usually amounts to only 1 or 2 cents an acre. 



By 1917 the time was ripe for correlating all rodent eradi- 

 cation activities in accordance with a unified but compre- 

 hensive plan. Work under the plan outlined by the Depart- 

 ment of Agriculture for the organization of cooperative 

 campaigns for the control of ground squirrels, prairie dogs, 

 and jack rabbits (Yearbook Separate No. 724, 1917) was 

 already progressing favorably in several States, and requests 

 were received from officials and farmers to extend the service 

 to include other States. Added stimulus was given the move- 



