The use of color to make poisoned baits more selective in rodent control and less destructive of seed-eating birds was demonstrated in Colorado and S. Dakota. In the latter area strychnine-poisoned baits were exposed in approved manner for the control of Richardson ground squirrels. Part of this grain was uncolored, part dyed yellow and part green. A search for poisoned birds on 8 exptl. plots disclosed 85 killed by feeding on uncolored grain and 9 by feeding on yellow grain. No dead were found on areas treated with green grain. Stomach examination of the victims verified the fact that green bait and, to a lesser degree, yellow bait are not as readily accepted by birds as the uncolored. Expressed differently, it was found that 77 pounds of uncolored bait killed birds at the rate of 1.1 birds per lb.; 45.5 lb. of yellow bait killed them at the rate of 0.2 bird per pound; and 19 lb. of green bait killed no birds.