In the Orchard and Vineyard

New Zealand Journal of Agriculture, Volume 68, Issue 5, 15 May 1944, Page 376

In the Orchard and Vineyard

Orchard Notes

Pruning Stone Fruits

THE pruning of stone fruits may be started as soon as the leaves commence to drop, at which period the growth should then be fully ripened. In practice there are so many deviations from well-defined systems rendered necessary by varietal peculiarities, physical condition of the tree, age, etc., that any definite directions are apt to be misleading, but broadly the general principles apply through - out, and by noting the fruiting, habit of the tree and its response to previous prunings any modification, necessary can be made on well-defined lines. Briefly, the objects of pruning are:— (1) To build up and maintain a physically strong tree of a size and shape best suited for convenience and economy in management. . (2) To maintain the balance between wood and fruit production, and ensure an annual average production of fruit of good size and quality. (3) To regulate or modify the growth, in order to obtain an even distribution of the fruiting wood throughout the tree. Peaches and Nectarines Peaches and nectarines crop on the previous season’s growth, both on laterals and short spurs; the latter are really very short laterals and are more , prevalent on the nectarine than on the peach, though some varieties of peach develop them freely. The important point, however, is that both laterals and spurs are good only for one season; consequently the peach must be encouraged to make ample new growth if it is to carry good crops. To obtain this renewal of fruiting wood the peach tree must, in the first place, be kept in good vigour, but much can be done by pruning to encourage the renewals in the most convenient places. In some cases the two-year-old laterals will have thrown out side laterals carrying fruit buds and they can be treated by one or two methods:— . (a) The two-year-old lateral may be shortened back, leaving one or more of these secondary laterals according to the amount of fruiting wood it is desired to leave on the tree, trusting to

the more or less severe shortening of the two-year-old lateral causing fresh growths to form during the following season to supply fruiting wood two years hence. (b) The two-year-old lateral is shortened less, leaving a greater number of secondary laterals, some of which are shortened to buds near their base to provide fruiting wood for two years hence and others being left to carry the coming season’s crop. This method is found especially useful in cases where the best fruiting secondary laterals are near the outer extremity of the two-year-old lateral and those near the base are carrying very few fruit buds. These latter near the base of the old lateral can be stubbed back to encourage fruiting wood, whereas the better fruiting lateral nearer the outer extremity of the old lateral can be preserved to provide the coming season’s crop.

Subsequent Fruiting Wood In some varieties many of the two-year-old laterals will develop many short side growths crowned with a cluster of fruit spurs. These should be shortened, leaving sufficient spurs to carry the coming season’s crop; the shortening will generally have the effect of developing fresh laterals that can be used two years hence. If the two-year-old lateral throws neither secondary growth nor fruit spurs, but only dormant buds, it should be cut hard back, leaving two or. three sound, dormant buds closest to the base, in order to provide subsequent fruiting wood. If, as sometimes occurs; the', two-year-old lateral develops neither secondary laterals, spurs, nor dormant eyes, it should be removed altogether, care being taken not to injure the ring at. its base where it junctions with the main limb. The removal of the lateral in this way removes an outlet for sap which encourages the wakening into growth of dormant eyes in the vicinity, sometimes right at the base of old laterals. In vigorous trees, especially in that part of the main limbs closest to the current year’s leaders, a greater number of primary yearling laterals will

be found than is required for the following season’s crop. ' These should be thinned out by stubbing them back- to a couple of sound buds nearest to their base; this will often result in . the formation of two weaker lateral growths. At the following season’s pruning one of these should be left to provide the coming season’s crop and the other stubbed back to provide new wood. The length of the yearling laterals that are left should be reduced if the tree is generally a heavy setter and if it carries buds well towards the base of the laterals, but with trees that usually set only a light crop, or those that carry fruit buds only at the tip of the laterals, they should be left longer or not shortened at all. - < Plums European plums crop mostly on spurs, either direct on the main limbs or on the two-year or older laterals. With many varieties it is preferable to leave the yearling laterals full length to encourage the development of fruit spurs. With others, however, it is better to shorten the yearling laterals slightly. Here again, the spurs on some varieties are only short lived, and it is necessary to shorten back the two-year-old laterals to help maintain the spurs and effect renewals. The Japanese plum crops mostly on the previous season’s growth and on spurs. It is, generally, an easy tree to manage, as not only do the spurs crop for several years, but they, are also easy to renew as they become spent. , Although the Japanese varieties will generally spur, even if the yearling laterals are cut short, it is preferable, if the trees are making strong growth, to shorten? only slightly as more spurs will then be formed and there will be less shoots to thin out at the following pruning. The two-year-old laterals may be shortened, or the yearly extension only removed to assist in maintaining the spurs and provide for renewals. Any laterals that have run bare of spurs should be removed as described in connection with the removal of spent peach laterals. Apricots The apricot bears fruit on the previous year’s growth, and many varieties also carry their crops on spurs which last or naturally renew themselves for more than one year. Some varieties under certain conditions, indeed, develop , very few spurs, their cropping, being chiefly on the previous year’s laterals; in such cases the management is similar to that of the peach. With the spur-bearing class it is generally necessary to shorten the two-year-old or older laterals to develop the spurs they carry near the base and to encourage renewals. • J —A. T. DOUGLAS, Acting District Supervisor, Horticulture Division.

Citrus Notes

Harvesting and Grading

117 THERE infestations of the main WHERE varieties with the wax citrus varieties with white wax scale have appeared the numbers of scales - present may vary from scattered individuals to serious infestations in cases where their populations have been built up over several seasons without successful control measures being taken against them. Spraying If a control spray was not applied in the latter part of April, a thorough application even now will do much to reduce the carry-over into next season. An autumn Bordeaux spray, 3:4:50, should be applied towards the end of May or in - early June. < This spray should cover all parts of the trees to obtain the best results, the main object of its application being to control brown rot. Accordingly, in the event of circumstances limiting the

time which can be devoted to ; this spray, the trees should receive a careful covering at least up to four or five ft. from the ground. The fruit. and foliage of the lower, parts of the trees are the most likely to be attacked by citrus brown rot. , Lemon Harvesting The coming month should show a definite upward trend in the quantities of lemons ready for harvesting. With the peak of the season approaching it will be well to keep early winter picking as 'close, as possible, without taking immature , lemons, in order to distribute harvesting as evenly as can be managed over the busy period. Well-planned picking can. help labour problems in the

orchard, while assisting handling and marketing as well. Packing Shed Equipment Simple equipment, designed to speed up packing shed work without undue outlay for machinery, will assist growers with relatively small crops to handle and limited shed space within which to work. Many orange and grapefruit crops have increased in recent years from a few cases to moderately large quantities which, without provision of some kind. of equipment, must prove increasingly : difficult to handle. Nevertheless, while crops may have reached a volume not easy to cope with, in the absence of. any shed conveniences, they do not necessarily justify installation of sizing machinery designed to handle large crops. To deal with these intermediate quantities of fruit it is suggested that. the “long bin” system, or a modification of that system adapted to the space available, could be used with advantage and at little expense. “Long Bin' System The “long bin” system dispenses with preliminary sizing of fruit before it reaches the packer. It depends on,

packers developing the aptitude of sight-sizing oranges, and selecting those required for each case from the full range of sizes displayed in a shallow bin. While this may seem difficult to those who have not made the attempt, . skill in sight-sizing is quite easily acquired; in fact many graders now in the habit of sizing fruit preparatory to packing have already developed the art of sight-sizing to save time. Many growers have some device constructed to act as a sizing, guide, but in practice most people find that hand-sizing may be carried out satisfactorily with only occasional reference to the checking guide. The object of the “long bin” system is to reduce handling time, by simplifying grading, without appreciably slowing the packing. A long table or bin, with a top of sacking, is required. It should be '3O in. to 36 in. wide and about 33 in. high for easy working. The length should be not less than 5 or 6 ft. and may be considerably more to accommodate several packers. The sacking should be stretched fairly tightly so that there will be very little sagging when it is loaded with fruit. This will ensure that only a shallow pile of fruit will be on the bin at any time, which will make selection of sizes easy and will reduce injury to fruit which would be .caused by searching through a deeper layer for suitable sizes. First for Quality The fruit is graded first for quality, one grade being . put directly on to

the bin, if convenient, and the other into boxes which will be held until the first grade is packed. The packer then commences by selecting fruit of the predominant size for his first case. He starts at one end of the bin and moves his case along as he uses up the size on which he may be working. Some prefer a packing bench running the full length of the bin, the packer standing at the side of the case, leaning over it to reach the oranges, and having the advantage that the fruit is in view directly in front of him. He moves the case along the bench as required. If it is desired to pack from the end of the case, standing side-on to the bin, a movable stand with small casters or wheels on the front legs to facilitate its movement will stand firmly while packing is done. When the first case has been filled

the packer selects the next most numerous size for his second case, and so on. There may not always be sufficient of the largest or smallest sizes to complete a case from the fruit on the bin. It is best to pack part cases of these, to be set aside until more of the same size accumulate, rather than leave odd sizes in the bin too long. However, with a bin 8 ft. or more in length it is rarely necessary to put aside a partly-filled case. With a little practice packers readily develop the art of selecting fruits of the sizes re-

quired for the various packs, soon learning to take advantage of the slight permissible variations of size within a case to bring the finished pack to the desired level. Sight-sizing Necessary In actual operation sight-sizing is necessary with most home-made contrivances, even to the smaller mechanical sizers. Few of the machines in use are capable of sizing flattish fruits, such as New Zealand grapefruit, by any means accurately; consequently two or more counts are usually packed from each bin. The “long bin” system demands merely a fuller development of the art of sightsizing, and facilitates this by displaying the fruit on a shallow bin, and causes less mechanical injury to the fruit. Quality grading, without the complication of hand-sizing at the same

time, becomes simpler and quicker. With a few days of experience a packer will find his speed little, if any, slower from the “long bin” than from the bins of a mechanical sizer delivering poorly-sized fruit. The “long bin” system is not new, but has been used by packers of large, as well as small, quantities of various kinds of fruits for many years, being especially suitable for handling stone fruits and tomatoes. It is recommended for trial by orange or grapefruit growers who may be experiencing difficulty in handling crops with existing equipment, or who have not yet provided for the packing of their crops.

—I. L. NOTTAGE,

Orchard

Instructor, A\

Mckland.