DESTRUCTIVE PESTS

Evening Post, Volume CVIII, Issue 117, 13 November 1929, Page 21

DESTRUCTIVE PESTS

WHITE ANTS OR TERMITES

-AUSTRALIA'S PROBLEM

I Australia is confronted with a problem that happily does not concern New Zealand. This is how to combat the ravages caused by whitu ants, and energetic measures aro about to be taken with a view to lessening the huge annual loss caused by thoso pests. Judging'from the data already collected the damage is perhaps iveu more extensive than is generally believed. For instance, slightly over °„UOO,OOO telegraph and telephone posts had been erected in Australia to date, and of these the average annual replacements amount to nearly 70,000. When it is remembered that, the average cost of each replacement is upwards o £2, the extent of the total replacement cost will be realised. Moreover, these costs are likely to increase in the future rather than to diminish, for a considerable proportion of the poles already erected have-been put in place luring the last ten years—corresponding to the rapid increase of the telephonic and telegraphic services of the Commonwealth —and they have not yet reached the replacement stage. Few authentic figures as to the "cause of pole failures are available, but it has been estimated that while various, rots perhaps constitute the most important cause, white ants are responsible for some 30 per cent.

In Western Australia, where over 9,000,000 sleepers had been laid by the year 1928, the average replacement figure is in the region of 2.5 per cent., or. 225,000 sleepers (costing about 5s each) per year. As the total mileage of railway .track in Western Australia constitutes but a comparatively small portion of the. track of Australia the annual cost of railway sleepers alone must, therefore, constitute a fairly serious addition to the expenditures of the Australian railway /stem regarded as a whole.

Other-public utilities, for example, authorities responsible for harbour structures, highway bridges, etc., are, of course, facing-problems of a similar nature. In;addition, there is the large annual loss caused to private interests and individuals. As instances of losses of^this nature, the-serious damage to the tens of thousands of miles of fencing posts of Australia, and the damage to private 'houses, particularly in the northern parti of tho Continent, may be mentioned. Comprehensive statistics regarding the private losses due to replacements are not available, nor is it probable that, they ever will be. It seems very safe-."to assume, however, that whilj the losses to public-utilities caused by white ants, borers; and rots aro large, the losses to which private interests are put on account of similar agencies are even more so.

Mr. G. F. Hill, who is well known as an authority on Australian varieties of termites, or white1 ants, of ;which there are about a couple, of hundred species, has Dr. Tillyard's endorsement of a plan of campaign. He says:— "My proposal is that I should undertake a description of the undeseribed species at present available, or which may become available- from time to time, as a definite part of my work, so that our knowledge should be at least as adyaneed.as is required by the Forests Products;. Division. Preliminary work could be" undertaken concurrently with the above to determine satisfactory methods-of testing colonies in captivity. At present we know practically nothing of .- this probably cheap. and easy method ,of conducting timber tests.' My personal view is that termites constitute a problem in the insect world second only to-th- blowfly in economic importance. It affects every State, with the possible exception of Tasmani^, and a very wide range of interests. Unlike- the spectacular- outbreaks of pest such as thrips, peach aphis, grasshoppers, etc., which occur only periodically, and generally in areas in which the population is large enough to make its voice heard, termites work continuously, and their damage passes more or less unnoticed until - remedial measures are hopeless. ..."

It is of interest to note that the white ant problem has aroused concern in several countries- other' than Australia. In the United States, the Madison. Forest Products Laboratory has recently initiated a programme of research with a view to testing the effect of treating timber with various chemicals as a safeguard against the pest. Small pieces qf several varieties of American timber have been treated with chemicals in various ways, and these, together with untreated pieces of the same v.a-rieties. to serve as controls, have been sent to different localities in America, and also to South Africa and Australia, for imbedding in white ant colonies and. for the observation of the results.