ORCHARD PESTS.

Dominion, Volume 7, Issue 2010, 18 March 1914, Page 10

ORCHARD PESTS.

WOOLLY APHIS KEPT IN CHECK. ,• (By Coleman. Phillips.) My orchard of about one thousand trees surrojiiids the house,, and I found lately that the two lengths of garden hoso (COftV each), from the lugh-pressuro water -!taps, would command most of .tho trees. . I had tried everything against the woolly aphis (all the oil remedies , ,' in fact), and Vailed. lam lipt 'successful with kerosene omulsionniaking!'.." Sometimes it goes well; sometimes badly; and I think this is tho general experience. But it is a ,y,ery .useful remedy to hare ready at 'hand.'"~ ; In spito of all I did, the trees were growing worse, so I resolved upon hosing:' tho aphis off with plain cold water/ The effect is simply marvellous. Tho trees remain clean for three weeks to a month, when I give them another hosing. I must say the appear to enjoy, their bath. I hoso four times in summer (December, January, February, and."March).," as it is in these months tho: aphis increases. But the plan is , ' to hoso 'whenever it shows itself at all badly, ieven onco a' we'ek. Two.boys get'ovpr' tho orchard in a couple of days;"one hosing, the other searching' out ahead; and also going over the trees that'have been hosed, to discover missed spots. .

. ' I try; and hoso just before the arsenate, for codliu moth (not that I believe in the arsenate at all, as I'will show directly, but.am compelled by law to do.it). After hosing a tree, churn up the'soil beneath it, with the water, for a little, to bury any of the aphides that are washed off. Tho hosing gives the trees a drink when they badly want one; if! does not kill any natural enemy (for these, unfortunately for us all,.are' conspicuous now by their absence), and it 'washes off a lot of other germs hostile to:!the health of tho tree. The strong jot of water cleans out spiders,earwigs, aphides, et hoe genus omne, which congregate near the fruit buds, and the whole tree looks as clean as a new pin. These harmful aphides give in'to iiothing but force, aud most of our spraying pumps are of little use. An oil-engine force, or motor-pump, costing anything over £100, is too exsmall orchardists, but those .-pumps'would give an'orchard a wash-, down once a fortnight quite well and easily: ' ,'lt is this plain wash-down I recommend, no matter how it is done, as tho rain has not force enough to dislodge tho woolly aphis.' I advise anyone planting a young orchard to give their young trees a thorough hosing, as the great thiag is to clean these young trees from the ter-' rible pests distributed through the Dominion.' On the young trees are sent out woplly aphis, black aphis, silver blight, etc., etc., and every orchard evil in fact. It is simply shocking what is-happening, as I see well now from my own orchard. The light I have , had against black aphis alone these past two or three seasons, upon the.peaches, .nectarines, an.d some plums, just bought from the nurseries is enough to break any ordinary,heart; and I absolutely failed. Now lam going to try plain water-hosing- with -force ' (I used: every kind of spray recommended without success against "black aphis, and I did not like to resort to cutting down the trees, which is often done now). ■< ' ■ i vi" ■.-■-.

Present'Pest-Fighting Methods. We are all making a. terrible mistake in fighting these harmful orchard pests as we are doing, ivith various sorts of poisonous or iujurious sprays, which kill the natural enemies, and only increase thereby' the pests themselves. Poison is not Nature's remedy against anything; a natural balance of prey upon prey has always to be aimed ?or. I "found that the case in 1879, when I had to fnce the, rabbit pest; and it was tho natural'balance I aimed at and conquered with, at Dry- Kivcr. ( In Australia, they ai'o poisoning the wholo Continent; not reducing their rabbits, but increasing their blow-fly, grasshopper, caterpillar, aud . other noxious pests).-

About a year or more ago I wrote the Hon. Mr. Masscy, asking whether I could not breed the natural enemies for myself (chiefly tho various lady birds, which [.years ago wero so numerous, and now we hardly see). Forty to fifty years, ago plums and apples grew in prpfusioh, and peaches rotted under the trees.," "There were no .pests. Now, in ,spito ,of. all tho poisoning, it is more and more'difficult to grow a fruit crop. Tho Prime Minister' referred my letter to Mi 1 . Kijjc; who replied to the effect -that it would bo too expensive for a- . private settler to ertct aud look after one of these breeding-houses, as it would require a biologist's constant attention the whole year round. I i.dmitted: this, and dropped the 1 matter. But surely the orchardists could get together,-, and erect for themselves, for each district, 'a breeding-house for tho natural'enemy, and steadily turn them out. ■'• They would find that courso far moVo economical than the constant spraying, and-do far more effective v-wk. Then add the herein-suggested plan of' 1 washing down the trees with cold water once a fortnight, and I am sure we .should get better results than we are getting now. v Even on ,1 hundred-acre fruit farm, ■ the h.p.-pipo reticulation would not be found very expensive. But .orchardists should try tiro plan on one "or .two .trees, and see the effect for themselves. I must say lam exccedmgly pleased with it, as it thoroughiy checks the spread of woolly aphis, and does the- trees a lot of good. Therois not the slightest doubt in my mind that tho constant harmful sprayings -wo resort to is bringing a lot of ovif upon us, exactly similarly to the wholesalo way they are poisoning tho Australian continent against tho rabbits brings upon them grasshopper, blow-fly, caterpillar, and other harmful pest's, absolutely unknpwit to them thirty or forty years ago.' I have for a'quarter of a century past pointed out their mistake to them, but they aro all so wedded to tho poison (just as we aro here in our orchards) that there is 110 taking them away from it, And. here am I in New Zealand compelled, against my will, to pour about 201b. of arsenate of lead annually over my fruit trees, which in tho end must sterilise the ground, and absolutely destroy any fruit crop. For arsenic is a mineral, not a volatile poison, and must remain where it is sprayed.

1 do not say that hosing washes all the aphides out of tho crevices, because no force will do that. Only the searching little feelers and mouths of tho natural enemy will get into thesecrevices; wherein lies their .enormous uso in. upholding Nature's balance. What I do affirm is that the hosing so keeps down tlie woolly nphis (and also washes off other harmful pests) that the evil is under control, and the next season's fruit buds are not injured. I do not say that we can entirely do without arsenate, Bordeaux, and red oil just yet; but I suggest that we turn our attention to • gradually dispensing with them, by breeding and turning out,tho natural enemy all over tho Dominion, and then hosing our trees with plain cold water. Amendment of the Act Urged. AVhoro there is no high-pressure water supply it would be necessary to erect, a tank or two and windmill, on the highest, point, of the ground. Use i.tho smallest garden-iiozzle in hosing, as

it is force, not quantity, that does the Rood. In spraying with arsenate, I use about 100 gallons, so that double that quantity of plain water would get over a large area of small trees. It is the smallest trees that require the hosing, so as to prevent the growth of the unsightly knots, although, I first cured , my big trees with the hosing. I think Parliament should' amend the Orchard Diseases Act, 1908, in the direction of compelling all nurserymen to thoroughly hoso as well as spray, all their young stock, whilst in the nursery beds, and before sale. That would tend to greatly reduce the spread of woolly aphis and other ■ pests. . They can 'hand-paint if they like, but they should also hose with force. The Government, which has a considerable number of experimental farms, should try hosing under high pressure once a week, to see whether that would not control oven the codliu moth, just as well as tho arsenate of lead, which wipes out any chance of" the natural enemy getting in its most beneficial work. The- object is to see whether a weekly high-pressure -hosing with plain cold water, combined with the breeding and steady turning out. of the ladybirds, would not better control all insect pests in any orchard than tho present harmful poisonous sprays. All I can now affirm is that the hosing thoroughly controls woolly aphis, and a control of this pest has been vainly sought for all over Australasia for years past. In this articlo all I do is to give tlie results of my own practice for the benefit of orchardists. The woolly aphis is not exterminated, but it is kept thoroughly in check. With the further help of the lady-birds, when turned out, it will bo possiblo to reduce it to harmlessness, as we have done with the rabbit. . '