THE WOOD BORER

Dominion, Volume 12, Issue 192, 9 May 1919, Page 9

THE WOOD BORER

* HOW TO CONTROL IT.

Various timbers are often destroyed through the ■ larvol activity of certain beetles popularly'known under the general name of the "wood-borer," says ■•Mr.* A. 11. Cockayne, biologist, writing in tlie "Journal of Agriculture." Timber affected with tiles,? insects is often said,to 'bo ■affcetsd with dry-rot , , a term that Teally should bo used.only when tho damage is caused by ono of the timber-rotting bnsidiomyceros. It is generally considered that an introduced beetle, cosmopolitan in its distribution; and known scientifically as Aiiobinm domcsticuin, is the mio mainly responsible. -There are, however, many -Sow Zealand species of Annbium, and , several of these undoubtedly cause considerable damage. The oxtrcmelv bad reputation that tho Anobiiim wcod-bprer has gained as a timber-destroyer is due to tho fnet that it is extremely, partial in its attacks to the New Zealand white pine (knhikatea) nnd kauri.' As both these timbers were commonly used in house construction in tho earlier days of settlement, the wqodboror soon became a serious consideration. So 'bad are its ravages'on'white pine, especially any that may contain Enpwoad, Hint this timber fell 'into plefo disuse for internal 'house construction. For many years while- pine was almost unsaleable, end it was not until tiie advent of export dairying that this timber again became valuable. Anobium domcsticuin is likely' to bore into a very .■ large variety of' timbers, especially-any , that may contain apprc> ciablo amounts of sugar in their wood cells. In general, however, it is only in white pine nnd kauri that the most extensive damage- is done. In both these timbers gcod heart wood is likely to be affected, but -with other timbers, such as red nino (rimn); only the wip at times is likely to bt.come riddled with the larvae of tho 'beetle. When timbers aro stored for .many .'.'years;, without much freo ventilation species not normally affected may be-atfneked. This has weil been shown in museum; material from time to time.

The life history of Anobhim domeslicum has not tali worked out in detail m New Zealand, but it here seems to follow much the same lines as in Europe and America. The. larvae, after tunnelling and feeding in tho timber from ono to three, years, emerge during the monthsof November and December. During this period u good niariy may be swept up each day from- the floors of affected houses. The beetles each day lay from eighty to ono 'hundred and'fifty eggs. This will be'-dono in ;ereviees in the'wood, or short bore's will bo made, and several eggs deposited in each hole. In affected timbers tho eggs'-'are frequently laid inside old , tunnels,' ,'aml this often makes it impossible to spray for killing tho young larvae More tliey enter the wood. Anobiiim domesticum is not really single-brooded, but as beetles usually emerge, eaoh'early summer'it is generally looked upon as such. Tho control of wood-borer falls under two headings—(l) in house or building timber, and (2) in movable furniture. So far as wood-borer treatment in building timber is concerned,- this is yearly \iecoming of less importance. The majority of tin; old badly infested houses have been replaced by buildings in, which whito pine is no .longer, used. It is only occasionally that renovation of badly infested buildings can be satisfactorily undertaken. The replacement of. floorings and linings with red pine or black piiie (matnij can, however, be done at times. When infested material is rr.moved it is best done in late autumn to eariy.spring, and the timber removed should be destroyed as soon as possible. The joists,. etc., should be sprayed with a solution of arsenate of lead, using it at the rate of lib. to 28 gallons of water. In houses where only one. or two hoards are att'octed T always "recommend the removal of the affected timber rather than to attempt any direct control, If, however, the cost of doing so is prohibitive, the affected wood should he sprayed in November,- December, and January three times with a mixture of benzine and creosote, Using fivo parts of henzine to ono of creosote, or a".'mixture of benzine and naphthalene, dissolving about the equivalent; of two moth-balls of naphthalene to every, i pint of benzine. Spraying with.'arsenical compounds is'.of ten recommended,-hilt the habit of the beetle laying its : eggs in old tunnels often makes this method- unsatisfactory. The adult beetles appear to feed very little-, I'j'd any poisonous spray must kill Ihe larvae emerging from the eggs . rathei than the mature insert. .

So faraS'luniitiire is concerned, a word of warning, against. thp purchase of sec-ond-liaiul furniture is necessary. In many cases such furniture will bo the means ot-l-introducing borer. Cure should always bciakon to see that any .such furniture is 'sound'before introduced into a house. ■Borer in cha,irs, tables, pianos, and other articles of furniture should he systematicnlly treated. Benzine and creosote squirted into lach hole with a small pipette, and then the entrance stopped with a peliet of soap, will liu found the best treiitniont to adopt. .Where the wood is extremely badly affected it will bo best to Ret rid of the article rather than try'to control the borer. A very sQbd method of dealing cith Hie pest i.-i to 'kepp a sharp loo'liclit for the appearance of any-dtist oi- frass beiiiK ejected from the holes. Whenever, this A'cure the ln.rvao arc very easily reached with an application of benzine, and treatment directly such dust appears is often entirely snl'isfnctorjr, <W VHW only onc« appliedi