Show o 0 oTO TO JULL JULIJ PESTS WITH V WAR An GAS Experiments on the use of poison gases for exterminating obnoxious birds rodents and Insects will be undertaken undertaken un un- un en this tills fall tall by the U. U S S. S biological biological bio blo- logical survey y in cooperation with the chemical warfare service The method will first be be tried on blackbirds blackbirds blackbirds black black- birds in the Imperial valley of Cali Cali- fornia In that region we are told by Chemical and Metallurgical Engineering Engineering En En- New York these birds are said sald to todo do at least worth of damage each year It Is impossible ble ble- bleto to destroy them with poisoned baits haits but as ns they roost on the tho reeds in the marshes It is thought that they can be killed by a gas cloud at nIght when the wind is favorable Says Says' the paper named above The blackbirds are migratory and return to the same places year after year It Is thought that a big killIng kUlIng killing kill kill- Ing in a certain locality will probably free It of the tho pests for many years A AA few other birds in the blackbird blackbird- Infested marshes marsh will wUl be killed at the same time but the department believes believes believes be be- that these local birds will soon reach their normal numbers again Arrangements also aro arc bo being ng made by the biological survey with the chemical warfare service for Investigating investigating Investigating gating the Ule possibility of using poison poi pol- poison polson son gases on such burrowing rodents rodents ro 10 ro- ro dents as rats prairie dogs squirrels and woodchucKs Tests Testa on pocket gophers and squirrels ground-squirrels hy by these two cooperating branches of ot the government In California show that chlorine may be used with good results If h handled properly The chemical warfare service used phosgene gene eno on rats in Porto Rico with promising results Some of these war gases will b be compared with carbon carbon carbon car car- bon for tho the killing kUlIng or of woodchucks and other rodents in their burrows |