HOW FAR CAN A WIREWORM'S MOTHER DIG?

Chronicle (Levin), 11 June 1946, Page 4

HOW FAR CAN A WIREWORM'S MOTHER DIG?

LONDON. For 13 days tliree heetles have been burrowing their way aeross a Hertt'ordshire field, and, tliougli 110 human eye ever sees them, their underground pro- ! gress has been recorded every day — to the i-neh. How? By meaxrs of a 1000-volt cleetric lieetle deteetor operated on the sanie prhiciple as a mine deteetor. Why? Beeause these insects are among the worst pests known to farmers, and if the distanee they travel in a given time can be diseovered much can be done to limit the damage they inflict on crops. The danger'limit round wirevvorm-infested lields can be fixod. This vitallv important test is being carried ont by scientists of the Rothamsted experimental station at Harpenden. The insects are click beetles, each one of which is capable of breeding 10U wireworms. And each has five-millionths of a grain of radium fitted in tiny aluminium cont'ainers under its wings. rfhat is enougli to iast for 1400 years of travellijig — if need be. The beetle deteetor 's real name is the Geiger-Muller eleetronie discharge tube, and it was invented bv Mr. G. A. R. Tomes, of West Wickham, Ivent. A delicate glass tube containing a sensitive rod, which is electrified from an ordinary eleetrie point, is passed j over the spot where the _ radio-active befetles are believed to lie. As it gets nearer a signajl box gives 'out high-pitched ringing notes. At the j point where the signals are strongest | an rdentiftcation peg is stuek into the j grotmd and the past 24 hours ' progress j noted. | Progress to date is: Beetle No. 1, j 9ft; No. 2, Gin.; No. 3, just over 5ft. j Thfeir progress, like that of human i beings, is governed by age and litness. i One of Rothamsted's scientists said that other pests might be tracked down I'ater bythe sanie apparatus.