ORCHARD AN VINEYARD

New Zealand Journal of Agriculture, Volume 71, Issue 2, 15 August 1945, Page 195

ORCHARD AN VINEYARD

Essential Spring Work

PRUNING will now have been completed by most orchardists. If not, the work should be pushed ahead as speedily as possible in order that the orchard can be cleared of all prunings and other rubbish, ready for the spring operations of spraying, cultivation, and manurial treatment. Success in spraying is dependent largely on strict attention to details and should be carried out in accordance with reliable recommendations. Disease Control Some of the essential points in disease control are: — 1. See that the spray outfit is in thorough working order and capable of the required output and pressure. 2. Care must be exercised in the measuring and weighing of all spray materials and in the mixing prior to application. 3. All portions of the tree should be thoroughly covered. 4. Only certified materials should be used. Disease control is one of the most important orchard operations and demands constant attention throughout the season. Relaxation may prove costly not only in the failure to produce high-quality fruit, but in the extra cost of packing and grading. It is recognised by all commercial orchardists that the early or foundation sprays up to the blossoming period are of vital importance for the control of fungous diseases, and although there is a tendency in some districts to delay the first spray as late as possible, this cannot be re- . commended. Spores of fungous diseases as well as insect pests harbour under bud scales, rough bark, dead' twigs, etc., and are * only awaiting favourable conditions to commence their destructive work. At this time of the year much stronger dilutions can be applied to fruit trees than later, therefore a good application early, when the trees are just starting into growth, will often prevent trouble as the season advances. When to spray and what dilutions to use will be exercising the minds of growers during the latter end of the present month and early in' September. Actually growers should be guided largely by the results obtained during the previous season, ' and if

these were successful, there should be no occasion to alter their programme. There is a decided variation in local conditions and sprays recommended in these and subsequent notes are intended to apply under average conditions. Where trees are in a debilitated state through lack of general attention and other causes it may become necessary to modify the standard recommendations, but not to an extent that would impair disease control. Therefore, every effort should be made to bring debilitated trees back to a good state of health by paying attention to other essentials. Powdery mildew, for instance, is more often the result of general debility, rather than the cause. The trees can best be brought back to a good state of health by hard and detailed pruning, better cultivation, application of adequate fertiliser, and attention to drainage. Winter oil at a dilution of 1-20 is recommended for the control iof scale insects and red mite. It is important to obtain a thorough coverage of the trees where San Jose scale is present. Where there is no evidence of scale insects the use of winter oil for red mite control depends on the extent to which eggs have been deposited during the previous autumn. Care should be taken ,in using winter oil to see that there is no bud movement, otherwise damage may occur.

The use of Bordeaux mixture 5-4-50 or lime sulphur 1-30 as a base or foundation spray is recommended for the control of fungous diseases of both pip and stone fruits. Bordeaux mixture is recognised as the better fungicide and should be used except possibly for varieties which are known to be susceptible to spray injury. However, even with these varieties, if applied at the correct time, possibly a little nearer the delayed dormant stage than the greentip stage, no damage should result. Cultivation and Drainage Good and early cultivation is very necessary for the conservation of moisture, and if this work has. not already been done, it should be proceeded with as soon as conditions are favourable. Cultivation should not be done under wet conditions. Cover or green crops should be ploughed in as soon as possible so that the trees may benefit from these crops when they start growth in the spring. Trees should be dug round to eliminate weeds or other volunteer growth providing coverage for bronze beetle and other insect pests. Drains should be inspected and where necessary should receive attention. Where arejas are wet lying drainage should be provided, as trees in these areas are often affected with wet feet. Grafting Where growers are contemplating re-working fruit trees they should select scion wood from trees of good growing and cropping habits and as far as possible free of disease. Grafting operations should not commence until the bark lifts freely. x

—D. J. HOGG,

Orchard

Instructor, Mapua.