WORK FOR THE COMING MONTH.

New Zealand Journal of Agriculture, Volume XIII, Issue 2, 21 August 1916, Page 149

WORK FOR THE COMING MONTH.

THE ORCHARD.

J. A. CAMPBELL, Assistant Director, Horticulture Division

The earlier part' of September can, where necessary, be devoted to the completion of certain orchard-work which through unavoidable circumstances may have been impossible to attend to earlier in the dormant season, such as the application of winter sprays and the pruning of pip-fruits. Even the pruning of stone-fruits, although the trees are in bloom, may be continued where necessary. But to adopt this plan unnecessarily is a great mistake ; not only does it create many unnecessary problems, such as “ My trees are bursting- into bloom: is it too late to spray with oil?” or Should I spray with Bordeaux , first and oil afterwards?” and so on. The advance of. the season brings with it more than sufficient seasonable work to keep the average ochardist fully occupied, and much of the • future welfare of the ‘ orchard depends upon the manner in which the work at this period is carried out, particularly that in connection with the control of black-spot and other fungus diseases.

The principal work for the month will include—Cultivation; the application of a fungicide for the control of peach leaf-curl, and fungus diseases affecting the English plum (where this work has not been completed during the previous month) ; the application of a fungicide for the control of black-spot and powdery, mildew in respect to those pip-fruits sufficiently advanced for the purpose; the second oil spray for the control of woolly aphis (where not done during the previous month) ; and grafting and planting.

CULTIVATION.

It must be remembered that spring ploughing is the last and most important instalment of this form of cultivation , for the season, therefore the work should be thoroughly done. . September, as a rule, provides the best conditions for the. depending, of course, on locality and climate conditions. Ploughing should not be done while the soil is wet and claggy, nor should it be deferred until the soil becomes more or less baked and hard through the

heat of the sun. The object aimed at in ploughing the orchard is to thoroughly break up and aerate the soil, and to provide the best possible conditions for the roots. For this purpose a more or less light skimming of the surface is useless. The soil must be worked as deeply as possible without, of course, undue injury to the roots. Even this is a matter which is often given more consideration than is really necessary. There are many instances where a little less consideration for the roots and a little more for effective work would result in considerably more benefit to the tree. Provide the proper soil conditions and the roots, in moderation of course, can be pretty well left to take care of themselves. •

Before commencing to plough gather up all prunings, &c. Ploughing should not always be done the one way ; cross-ploughing should be carried out in cases where autumn ploughing - has been done. In any case open up between the rows of trees and finish up ,by throwing the furrow away from the trees. This can easily be levelled off by the proper manipulation of the disk cultivator. Work as close up to the '.trees as can be done without injury, in order to reduce subsequent hand-work.

After ploughing, the soil should be worked down to a fine tilth and uniformly consolidated. No cavities or air-holes are to be found in a well-cultivated soil. The soil-particles, although not packed hard, should lie in close contact. 1 In this way the requisite amount of warmth, air, and moisture is more satisfactorily provided and the conservation of moisture most readily maintained. Such implements as the disk cultivator, Cambridge roller, clodcrusher, harrows, &c., are used according to' the nature of the. soil for breaking down after ploughing. How soon after ploughing this work should commence also depends on the nature of the soil. With some soils, such as those of a clayey' nature, this is an important point, and one that requires watching very closely. If commenced too soon the soil will be found' to be stiff and puggy, and if left too long it will bake in the sun and become absolutely impossible to work , down satisfactorily in any way. With lighter and freer soils the question is much less important, but under any conditions successful cultivation includes working the soil down to a fine tilth.

SPRAYING.

Peach Leaf-curl. — Spraying for this disease should be done during the month of August, but although the majority of peaches bloom during that month there are quite a number of varieties that do not properly bloom until September. With these spraying can now be done, and in any case it is better to spray, even

though the trees are in full bloom, than not to spray at all. For this purpose use 8-6-40 Bordeaux mixture, or : lime-sulphur 1-15 to 1-20. For plum-rust, bladder-plum, &c., spray as for the peach. - 1

Black-spot. — This well-known fungus disease is accountable each season, directly and indirectly, for, a very large quantity of damaged and blemished fruitdirectly by the damage done to the fruit by the disease itself, and indirectly by the scorching of the spray on the fruit and foliage in the attempt to check the spread of the disease. Of the two the spray-damage is probably greater than that caused by the disease. . This of course does not mean that spraying should be discontinued,. for if such were the case the damage done by the disease would in a short time be very much greater than the two combined. The object to be aimed at is to control the disease and at the same time reduce the amount of spraydamage to a minimum. With this in view it is advisable to reduce as far as possible the necessity of summer spraying; but when such is required select a formula best calculated to check the' disease with the least amount of damage to the fruit and foliage. . .

Actual ■ outbreaks of black-spot can best be guarded against by thorough spraying with stronger fungicidal sprays earlier in the season, the most satisfactory time being after the buds burst and are showing colour, or . when the' most advanced are in full bloom. This state of bud-development, so far as a number of varieties of apples and pears are concerned, can be expected during the latter part of the month. Watch for this and spray thoroughly, and you will to a great extent provide against attacks of blackspot. The sprays recommened for this purpose are — I Pears : 6-4-50 Bordeaux mixture, or lime-sulphur 1-15. ' Apples : 6-4-50 Bordeaux mixture, or lime-sulphur 1-25 to 1-30. .

Powdery Mildew of the Apple. Bad attacks of this disease seriously affect the health of a tree, particularly those of more or less weak constitution, such as the Jonathan. Some varieties are less subject to attack than others, but very few are altogether immune. Lime-sulphur has proved to be by far the best remedy in general use for this disease. The spray should be applied early, just as the leaves are forming, and should be repeated at intervals throughout the season. An affected tree should be well cut back at the winter ■ pruning to stimulate growth, and all affected parts overlooked at this pruning should be removed after growth commences, when they will be readily discerned owing to the . white powdery appearance of the foliage.

The strength of spray at this period is lime-sulphur 1-25 to 1-30. The spray may be used considerably weaker and still be effective, but when applied at the strength stated it also acts as a control for black-spot.

GRAFTING

Unsuitable varieties of fruit-trees can by means of grafting be readily changed to varieties more suited to the requirements of the grower. Grafting can be applied to all classes of fruit-trees, but it is generally confined to pip-fruits. The work can be commenced during this month, or after the sap begins to move and the bark lifts freely from the wood. The process is simple, and has previously been described in the Journal. (See September, .1915.)

PLANTING

Planting can still be gone on with, particularly in respect of pip-fruits. Early-blooming fruits, such as , peaches, are better planted in August if the. soil conditions are favourable, otherwise it is better to hold them over until the soil is warmer. Before planting all young , trees should be dipped in oil emulsion, if this has not already been done at the nursery. The introduction of the regulations governing the sale of nursery stock, which have just come into operation, should in future do away with the necessity of the orchardist having to dip the trees himself before planting. However, until the regulations are in' proper working-order dipping before planting will be a wise precaution to thke.