WOOLLY APHIS.

Colonist, Volume LVII, Issue 13808, 1 July 1915, Page 8

WOOLLY APHIS.

AN AUSTRALIAN OPINION

Woolly aphis, or American blight, is one of the most persistent enemies of the fruitgrower. In dealing with it, more time is wasted to no effect than with any other pest. With proper treatment, and provided the trees are worked on blight-proof stocks, it should bo almost eradicated from the orchard on one or two seasons. Most orchardists have noticed that the red oil emulsion temporarily banishes the insect from their trees, and that it returns in weakened numbers during the spring months. In a short space of time it becomes re-established. The pest is protected by a downy covering, which, renders many of its number immune to; the effects of a mixture carelessly applied. The nozzles of the spray pipes must be directed close to the enemy, and the mixture forced into the crevices at a good strength, to make the application beneficial. The oil then penetrates through the downy covering, and gets to close quarters with its adversaries. Few aphides will remain active after such treatment. These will probably show in great numbers during the spring, at which time red oil emulsion cannot be used on the trees. The next attack must bo made with tobacco wash, and, if thoroughly applied, the aphis, if not completely exterminated, will remain in almost imperceptible numbers. Red oil, while one of the best remedies for combating the pest, becomes absolutely effective if used in combination with tobacco wash, well directed under good pressure. The latter formula, though it should not be used for some time, is appended, for it is unquestionably part and parcel of the treatment that should be adopted in combating this pest. Tobacco waste varies in strength^ but as a general rule one pound to four gallons of water will give a sufficiently strong mixture. The waste should be soaked in the approximate volume of water- for abcut a week before being used. The liquid is then made hot, but not boiled, for nicotine is a volatile substance, and its strength would be depleted by the escape of steam, and applied to the trees while warm. For young two and three year oJd trees, on which the aphis is not bad, good results have been obtained by going over them, and daubing infested parts with fat. Both red oil and tobacco may be used in the same way, when insufficient .aphis is present as not to warrant spraying.— "Penang" in the "Australasian/"