Koford 257 Cynomys ludovicianus September 7, 1955 Nr. Wellington, Colo. many spate the hedged Chrysothamnus & atriplex bushes have pail sediment around them by C.L. (such shode?); this adds to destruction shrubs. Denver, Colo. September 12, 1955 Visited Pred. & Rodent Control Dir., Ft. WL Denver, Headquarters, 2202 W. 32nd Ave., Neghland Station; talked with District Agent Roy Fugate and Asst. Dist. Agent Lebald Bowers, Most control of rodents finished August. Many shrubles and badges in state now. Formerly many C.L. in Kit Carson county. Now most work is "cleanup," there being no large number any county, white-tailed deer dogs being greatest problem. No diminution effectiveness 1080 on black-tailed prairie dog found. 1080 (made at Pocatello, Monsanto Chemical Co.) is going out of manufacture. Stockpile on hand, however, other companies may supply it. Fugate said company will sell only to goat agency because of dangers. (Don Spencer says that 1080 poisoned grain being distributed from planes in California, & that very high concentrations being used (2 oz./100 lbs. grain max. here).) Control of prairie dogs by salt thallium to 1946, then 1080 monthly; saw thallium still used. WPA & CCC camps did much rodent control work in Colorado, probably using strychnine poisoned grain mostly (to about 1940). With strychnine about 50% of bill on top of ground; 1080, 10% on top; thallium slower, mostly deliver ground (6-8 hours to kill says Spencer). (Spencer said 1080 poisoned dog shows no peculiar actions after eating poison but heart reaction is great at early stage. I secured literature on 1080 at Wildlife Research Lab.)