DISEASES OF FRUIT TREES AND THEIR CURE.

Patea Mail, Volume XI, Issue 131, 22 February 1886, Page 4

DISEASES OF FRUIT TREES AND THEIR CURE.

♦ ( Chronicle.') Professor Kirk, the Government Conservator of Forests, delivered a very interesting lectnrc on the above subject to an audience of nbont 50 of the members of the Progress and Indust rial Association, and others, on Thursday evening, in the Borough Council Chambers. Mr James Laird, Vice-presid* nt of the Association, preside I. The lecturer, alt r one or two pnratory remarks, plunged into his subject. Ho said they had. in considering the diseases of fruit Irres, to deal with fungi, insects, and diseases proper. THE PEACH. 'He referred first to 'he peach, because its failure was a matter of great mi portance, eff- cling, as it di ■!, a large reduction in the food supply of the colony. Excepting on the sea co >st and in places where there was abundance of shelter, the tree Ind suffered decay and destrue'ion in all pans ol ‘.he ejlnny alike. It was not a matter of a single year or a poit'on of adist'ict; indeed, the failure had been for son o lime ns continuous as it was widespna k Many ingenious itml plausible reasons had been put I'm ward to account for the failure. It had been al'iiiu’ed to a supposed deteriation of the climate ; but ho could not accept >hal conclusion, because, although tlry might hare had n gan'or ruin o.ll in one year than in anotho", the no turologica! i etui ns s(ircad over a score of years did not exhibit any sneli variation as lOuld he held to n a eliaily affect the eiiinat'’, A difference of tw«* in the summer heat, as in 1879 :>n 1 liriSt, would not account lor it. Why, in England, w here the ' liniaic was not nearly so favourable, there Was no such premature decay ot the peach as in this colony. He also nj-cted the insect theory. In England and Amciica the peach was i s liable to aphis attacks as lore, but it did not die out from the effects of it 'the peach suffered greatly from the giovvlh of fungi, but the < Cf. ot upon the true would not ho neatly so injn ions were it not that the tree was decaying from other causes. Ho was iodelted to Mr Anderson, of Wanganui, lor an ingenious theory which that gentleman had set up, hut he (Professor Kirk) was not able to accept it. It suggested that through severe weather the peach hid become coded with saline, matter, which had contributed to its decay. He must rp et this theory, because, even supposing saline matter to b' injurious, it could not he held to affect peach trees sheltered in the, dense forests iu the ci litre ot the Island. With regard to the hydrocyanic theory, hydrocyanic acid was not found in plants, and ho could not adopt the suggestion oven as a Working hypothesis. Wlttil lie himselt believed to be the real cause of tin* decay of the poach was the inherent vitality of the plant. It had been cultivated in China, its native country, for over 4000 years, and like, the po'nto in England now, and other [limits subjected for lon g periods to artificial treatment, it was losing its vitnlity, becoming subject to various diseases, and falling into decay. The cislom, which prevailed largely in some places, of growing p'aches on poach stock, was the most direct way of increasing the lack of vitality. After a description of the various diseases from which the peach suffers, the professor su’d thni cultivators should work upon the mussel stock (plum), which would give strength to resist the weather, and the attacks of insects and fungi. The mussel stock gave increased robustness, and Was what was now adopted by the principal nurserymen in England. Already it was being tried in New Zealand, and he was sure that in a few years nobody would think of such a tliimr ns working a peach on its own stock. The mussel stock was also the proper remedy for the almond, which was subject to the same decay as the peach. It would never do to work the peach upon the almond, because they would simply be working weakness upon weakness, as the peach was really derived from the almond. The apricot, again, should not be worked upon the mussel, but upon the Brussels slock. THE APPLE was liable to both insect and fungi pests. • In addition to the ordinary scale pest, he had discovered a large number indigenous to New Zealand. The remedy he would recommend was a small quantity of soot, mixed with castor oil, nnd applied with a brush to the trees. H(. preferred this to the American plan of using kerosene, which was injurious to the trees. The lecturer then wont on to refer to the Codlin moth, which he said had bent in the Auckland and Nelson districts for the last 12 years, and was unknown in this district. Simple paper bandages placed round the tree obstructed the progress of the moth upon entering t lie nnpo slate, and enabled it to he destroyed. For the beetle and the grass grub, the ravages of which latter were very serious in the Poverty Bay district, an application of caustic potash was the best remedy, or an infusion of the eucalyptus might be used with advantage. MISCELLANEOUS. The diseases of the pear were much the same ne those from which the apple suffered, mi I similar treatment should ho resulted to- Tne ring leech had worked terrible destruction in the cherrv and palm trees in Taranaki, the trees iii j one orchard appearing to be scratched I as if by fre. Hellebore w s the best I remedy, bn I it should bo frequently applied. The red spider was very troublesome in this colony, and such a season as the present was very favourable to them. Frequent syringing was the remedy, and almost anything would do to use. An emulsion of castor oil or a week caustic solution might be used in bad cases. The raspberry crop in the South Island was being destroyed by a moth, and the strawberry crop here was suffering from an aphis, which could be easily obviated by the application ol any simple solution. The orange in- ' dnstry in Auckland was being imperilled

by seed p'anling, and people were beginning to think that the climate v- 1 not suitable for the industry, hnt it v quite a mistake, as ho had tasted v fine oranges grown in the north o! .AOakland. With regard to the future of the fruit industry, he thought it was very promising. It should bo bom in mind that they will find mmkets in England and America when their fiuii. season was ov<r. In the fntuie they should give up the practice of growing tel! ti’ees, which were unsuited to our high winds and afforded facilities for tin ravages of insects. He hoped that before Png the local societies wou'd develop in'o a Colonial Fruit Growers’ Association, which might, hold conferences ?n li e diff. rent centres of the colony, !!ie Government should he asked to employ some qualifh-d peison to edit a report on the investigations of the association, and thus they would g I. the benefit of colonial research. After thanking the meeting for the interest and attention manifested, Professor Kdk resumed Ids seat amidst applause. Questions were thou asked, and remarks made by Messrs Sharp, J. T. Anderson, Q. F, Allen, P-wtsoh, L'fiitl n, Dixon, McWilliaro, and others, fn M’i lying, Professor Kirk said that hn!i an ounce of hellebore to a gallon o! water were the p opmtions for (he destruction of the slug leech. For strawberries, the caustic potash should be used in (he pronorth ns of to the gallon. He had not scon (he Brussels stock in N-w Z'aland, bn I lie knew an Auckland nursery man w-s importing •' 'or the apricot. It was tine, shat th<Lislon lemon was used for the (-range stock, hut it w->K t !, e worst that coni Ibe got. The bjiler orange and th ■ betg.iinoi were ihe best. The professor then answered tie various r<fe:eiu-s In and questions asked concerning the peach, and on concluding was awarded a hearty vote of thanks, on the motion of His Wmship the Mayor.