THE SOIL.

Nelson Evening Mail, Volume XLV, Issue XLV, 16 December 1910, Page 3

THE SOIL.

THE FRUIT INDUSTRY. BITTER PIT IN APPLES. A VALUABLE PAPER, The Fruit Expert to the Tasmania!! Government (Mr. J. Osborne, junc.), read a paper on "Bitter Pit in A.ppies" at the meeting of the Inter-< State fruitgrowers' Conference recently lie Id at' Hobart. The paper was published in the Hobart "Mercury.' 'and a copy of that journal has been forwarded by Mr. G. S. Haycock, of Bnightwater. A,t the last meeting of t'he Stoke Fruitgrowers' Association Mr. E. B. Izard, who attended the Conference, read Mr. Osborne's pa-per. The subject dealt with is of such importance to fruitgrowers that no apology is needed for the reproduction of the paper in full. Mr. Osborne said : WATER SUPPLY—IRRIGATION. The experience of growers in all fruit centres goes to prove that cair-efliess watering or .heavy intermittent showers incvease the tendency of trees to produce bitter pit. It is known that after a dry spell, during which, the ilow of sap is partially suspended, a heavy Tall of rain or an injudicious watering, will cause a great increase ifii the quantity of fruit pitted. This is said to be dus to the fact that the sudden rush o ' laii-ge food supplies ait a time when growth had practically ceased takes the tree, as one might say, unawares, and in the effort to accommodate sucli lacg? supplies certain of the' cells were destroyed, and bitter pit ensues. Where the treses are supplied with moist in equal quantities during- the growing season there will be, although, the supplies may be large, little harm dome. Itis im the unequal application that) loss will <aicrue. This is 'proved practically by the experience of grower s in disi'.'icts where the rainfall is evenly distributed ; there is always a certain quantity of water or moisture present in the soil, and' should an extra heavy rain be experienced tihe trees are in a condition to receive it without causing mischief. Where artificial watering is done it is best to -delay the application as long as can be done with safety, and when it may be no 10-ngto delayed the water 'slitoulid be applied steadily, filling the whole of the soil particles slowly, choosing the cooler .hours of the day; the early morning- is best, before tihe soil feels the influence of the sun. When the soil is well filled the water must be cut off, and in no case should the ground be allowed to become thoroughly dry a,£fai-n during the whole season. Only the most competent hands should- be employed, successful irrigation being a fine art. lit may be here mentioned that lan(d intended for irrigation should be well drained, as the moisture, to give the best results, should pai% freely through the soil. Where the lands are not too dtry in character, extra cultivation to cioiastirve the moisture in the soil is to be preferred to irrigation. There can be no douibt that water supplies to the orchard, dn the form of am artificial application ct ordinary rains hiave a great influence on the .prevalence of bitter pit, for during dry seasons the trouble is very much less, while in a rainy season, especially wbe-n the rains are heavy and intermittent, (bitter pits is very troublesome *and thi s makes the task of tcoanbating the disease very Hard.

EFFECT OF PRUNING.

Experiments cai'/ied out in. several districts in Tasmania prove beyond question that pruning has a marked influence on the prevalence of bititer pit, and as a consequence an entirely different system is being slowly evolved. Orchardists are regarding their younger t>.-ees wiith a curiosity born of the desire to lessen the trouble, and in places where it was the custom to cut back every yearling shoot in sigiht. the problem that is uppermost in their minds is, "How m-any of these cshoots can be removed with safety?" This question fn.n only be answered after a few years' experience, for pruning that is know® to be correct in on-ce case ■has been found useless in another. It is elea<r, however, that the trouble is Jess severe ' where from- 30 to 35 per cent, of tihe lateral shoots are allowed to remain uncut. These growths should be well distributed over the whole surface of the tree, and laterals that were likely to fcuit are chosen. These usually 'have the termbud in a fully developed condition, due to the fact till at, growth of wood and leaf in each case had ceased early in the summer, and thle whorl or cluster of leaves, usually three pla-ced at the extreme point, continue to draw upon the food supplies during the remainder of the /season, and store ud in- the terminal bud sufficient nutriment to provide, in most cases, a cluster of fruit-. The presence of rait on these shoots causes a considerable alteration in their position, bringing them to the horizontal • this lessens the rapidity of sap flow, anid in no case does the fruit become overcharged, consequently the loss fir-cm pit is practically nil. In a fe%v oases it has been found necessary to tie the shoots out, and the effect has been to increase fruitfulness in every case with no increase of pit. Such apples as Jonathan, Cox' s Orange Pippin, Rib-st-on Pippin, Sturmer Pippin, New York Pippin, WeYLington. Raidwin,, Duke of Clarence, Golden Reinette, and a few others, were treated in this way, the trees ranging f.rom five to nine yeairs of age, the time taken from planting in the orchard; a marked falling off in tne nuimber of damaged fruit being noticed. New York Pippin, which is very subject to the disease, *s beinw experimented with, and results will be° availalAe at a Later d'ate. A curious fact came under notice during a visit to a. Southern ordhard. Among same strong growing Sturmer Pippins was found one tree rather heavily laden on one side, the other side carrying ctnlv a few fruit- On examining the roots, it was found, that during draining operations the large roots on. that side of the tree were cut through about 4tt from the bole. A large number of fruits were set, and when mature these were quiie fcee from bitter pit, while on the lean side the apples (were well marked. Growers may their own ireferences from the fact mentioned, but , it seems to show that where supplies •>f food' are limited there is less likelihood of trouble from the pit. The whole investigation made, as far as trw management is concerned, Shows tihat bitte. pit is most prevalent on trees that have a vigorous upright growth and are closely and is least found. m. trees that are encouraged to bear fruit in proportion to their strength, that is, to crop as heavily as is consistent with, a healthy production of wood each OF AGE IN TREES. Close observation showte that the pit is most prevalent in young, strong, growing' trees, especially those produc--sig large leathery leaves; andeed, it

seams that the larger the sir.cead of leaf the greater the liability of the fruit to develop bitter pit. During the past yea; - , which was unfavourable to the precluction of pit, where tihe troublew?,;; traced the trees were welL Euippllied witli large leaves that excluded the light from certain portions of the tree, and no doubt, interfered with the natural development. As> the tr-ees age and< the number of fruit increase, the branches take on a. different habit, in mo?t cases .having a distinct leaning to the horizontal. This is more noticeable each veeur when, the fruift 'begins to increase in size, circulation! is retarded, and as time goes on, in many varieties the .pit disappears. In some cases, in trees, the pit wa® found to be very prevalent; New Y.'orfc Pippin and Welti niut-oji Pippin being very much affected. These trees -were over 40 years old. It was shown, however, that they had been heavily and; consistently Supplied with manure, which no dou.bt g avo rise to the trouble. Generally spe:ikin<g, it is found in Ta'sxno.nia- truut the trees, as age comes on, are less likely t.> be affected, except as before Stated. where manures are over-applied. The Chairman said that the paper was unquestionably one of the most illuminating and able that had been placed before the conference, and Mr. Osborne was to be heartily congratulated on his work. . ' Mr Thieie said he fully coincided with Mr Osborne's view, ;nid believed until they could control the weather tliey woiV.d not be able to control the disease. y t .v Re id (W.A.) moved:— That his Conference again, affirms the desirability of the Commonwealth C-vernment retaining tlie services oi j\ir McAlpine, the Victorian Governii- nt Pathologist, for the purpose pf investigating the cau.-e of bitter pit r.i; J bringing about a remedy for the disease.

Mr Tr.lly (Vic.) seconded the motion, and said it was highly, essential that Mr McAlpine's services should be retained. He had already done good work .and if they brought in a new man he would have cover the ground which Mr McAipine had already covered. He was in entire agreement with Mr Osborne, but last year 'he had had an experience w'hich rather upset his view s. He had two large orchards, one on Ihe Yarra flats, sn-d the other on a hill, with rather poor soil-. Last year, wh-ii fruit was being gathered, he noticed that the Bismarcks taken from the hilly country ran idly developed bitter p't when placed in the store. He ftonped the leathering, and went and examined the trees, and found that they were perfect iy clean. Alongside them were some Sturnier Pippins, which developed the diseri=-e badly, but they were clean. He considered that- they should continue their investigations, and do their ut-mo.-t to discover a remedy for the disease •

Mr T'hiele (Vic.) supported the moand it was agreed to. Mr Reid (W.A.) moved : That one delegate from each State be appointed by the 'Conference to continue the investigations into bitt'.r pit. and the informat'on so ga.inec. be h.-. nded over to the Federal authorities. Mr Tully (Vic.) seconded the motion, and it wa 6agreed to. Mr Osborne was given a hearty ; r ote of thanks for his paper.