WIPING OUT WOOD PESTS

Evening Post, Volume CXXIII, Issue 1, 2 January 1937, Page 21

WIPING OUT WOOD PESTS

"Knock, Knbpk," "Who's there?"— you' know the rest in 'its' umpteen thousand "variations. Science has now invented a "knock, knock" all of its own, , writes a correspondent in; "Reynolds News." The victims are wood-destroying insects—pests hated by every dealer in wood except the antique shopman. Confronted by a piece of wood and asked to report as to whether it was virgin territory or housed a thriving population of death watch beetles, the ordinary man would probably cut it to pieces to find out. Scientists attached to the Forest Products Research Board bring their radio valve amplifier into action. They listen in, and if the unlucky insects emit any "knock knocks" in their travels through the wood then the scientists clear the decks for action. They are perfecting a new way of wiping out the wood pests—by gas attack. Already powder post beetles, a deadly foe of the hardwood timber trade, have been "bumped off" by hydrocyanic gas. And before long it is hoped to get a gas concentration formula which will guarantee wholesale slaughter inside any wood that is treated.

Timl er c scientists are also copying war-time tactics and trying to starve the enemy, by blockade—by freeing timber .frorri .starch. . The powder post beetle likes plenty of it, in her diet. She iias.such -a keen nose for starch that, given the choice of two pieces of wood, one with less starch content than the other, she will nicely balance the number of eggs laid in each according to the commissariat available fcr the larvae. The death watch beetle, in spite of the fact that he has to go through life with the scientific name Xestoblum rufovillosum, is another wood pest that'continues to defy the experts. He iis the "tough guy" of the beetle world, and in some cases survives two or more treatments of wood with insecticides. In its annual report, the Forest Kesearch Board says that it may take as lone as 400 years for large timbers to dry right through to the core. It also explodes the idea that it is necessary to "bake" new buildings to dry them off. All that extra heat does if: temporarily to send down the moisture content, which is reabsorbed when normal conditions return.