Maintenance Work in the Home Orchard

New Zealand Journal of Agriculture, Volume 75, Issue 1, 15 July 1947, Page 49

Maintenance Work in the Home Orchard

By

R. G. HAMILTON,

Horticultural Superintendent, Auckland.

THE productivity of the fruit tree is influenced by numerous factors, such as temperature and climate; the texture and structure of the soil and the amount of organic matter, moisture, and acids it contains; the available supply of plant nutrients; and the extent of attacks by insects and diseases. Man can have little effect on temperature and climate but may greatly influence the other factors and by good management secure results favourable to the growth of his orchard.

THE general maintenance of the home orchard from year to year consists of cultural operations, maintenance of soil fertility, manuring, pruning, and disease control. Cultural Operations / , Cultivation is necessary to assist soil aeration and the elimination of soil acids and gases. Cultivation fosters moisture conservation by the elimination of weeds and other volunteer growth and by the provision of a soil mulch, but also facilitates the evaporation of excess soil moisture and is the means of incorporating green material with the soil to provide organic matter. ; As the home orchard is . seldom of sufficient size to permit of mechanical cultivation, the spade and hoe will be the main implements used by the average home gardener. The trees should be dug round at least twice a year, in autumn and early spring, and kept hoed throughout the summer. On the larger farm orchards which have been planted to permit mechanical cultivation, the orchard should be ploughed in the autumn, double disced in the spring, and kept cultivated during the summer.

Cultivation around such shallowrooted trees as citrus, passion fruit, tree tomatoes, and berry fruits should> not be to a greater depth than 4in., as their roots are very close to the surface. Because of the disruption caused to the young fibrous feeding

roots, spring or summer ploughing is : not recommended, and spring digging should be shallower than in the autumn. Soil Fertility The, fertility of a soil is influenced to a great extent by the amount ■ of organic matter which it contains. Organic matter is the main source of energy of the soil population, or soil bacteria, and from it the main supply of nitrates is provided by the action of the bacteria. The presence of or-

ganic matter, or humus as it is commonly termed, tends to increase the water-holding capacity of the soil in dry weather, yet facilitates the drainage of excess soil moisture. Further-; more, it improves the aeration and warmth of the soil and increases its power of retaining dissolved food substances. ' Organic matter may be said to be the basis of soil fertility and many soil troubles may be traced to a deficiency of it. Organic matter may be added to the soil in the form of compost, lawn clippings, leaf mould, . and stable and other animal manure, or by growing and turning into the soil some suitable green crop, such as,blue lupins, field peas, and vetches, oats, or mustard. ~ » 1 ' The correct time to sow the green crop will depend on circumstances. The most satisfactory period under normal conditions is during January or February so that the resultant crop will be ready (when the stems or straw have begun to develop fibre) for turning into the soil in the late autumn. On soils prone to 1 be very' wet in winter it is an advantage to have a crop such as blue lupins growing through the winter to act as a dewatering agent; for that purpose the crop should be sown in March and turned into the soil in August. Fig. 19 shows an excellent crop of lupins ready to be incorporated into the soil before the planting of orchard trees The most satisfactory method of incorporating green matter in the soil is by discing (on large areas), rotary hoeing, or chopping with a spade and then digging in. ' Ploughing the green crop under or trenching it, especially in the spring, is not . recommended, as the decomposing “blanket” of green matter tends to increase soil acidity and temporarily decrease the available supply of nitrogen when it is required by the tree in increasing quantities.

The soil may be regarded as the natural storehouse of plant foods, i However, as crops are produced the elements required as plant foods are' being continually withdrawn. Eventually those which are in greatest demand, or in shortest supply, become more or less depleted and the balance of plant foods is upset. Withdrawals of, plant nutrients ■. require to be replaced if success-, ful cropping is to be continued. Wise soil management and the - . addition 'of organic matter assist, . - . the liberation of further supplies , of plant foods by the natural processes in the soil. Manuring Where natural replenishment is insufficient the land should be manured to' offset the continual Tosses of soil fertility. Farm animal manures, plant and other refuse, meat works manures, natural and mineral deposits of fertilisers, as well as chemical fertilisers, constitute the chief means by which, replenishment may be made.

' Manures and fertilisers may be classified as nitrogenous, -phosphatic, and potassic, according to the main plant' food they contain, or as com- ' bination manures in which more than one type of plant food exists in quantity. Those which combine the three main elements, - nitrogen, phosphorus, and potassium, are usually termed complete fertilisers. Examples of the different groups are: — Nitrogenous Fertilisers Nitrogen Phosphate Potassium , , per cent, per cent, per cent. Sulphate of am- ' monia , .. 20.6 ; Nitrate of soda 16.0 . Dried blood .. 12.8 Meat meal .. 10.0 3.0 ‘ \ Phosphatic Fertilisers v Superphosphate - 7 20.1 Basic slag (20 per cent, grade) 20 . Bone char .. 29.7 Bonedust .. - 22.5 Potassic Fertilisers Sulphate of potash .. , 48.6 Muriate of potash/ ’ 50.4 Potash salts .. , 20 to 30 Kainit .. *4 Wood ashes .. 8 to 10 Combination . Manures Blood and bone (average) .. 7 10.6 Fish fertiliser ; (average) .. 6.0 12.5 Animal manures Considerable variation ac- \ cording to condition Fowl .. .. 18 to 36 II to 13 13 to 20 Sheep .. 12 to 16 6to 7 3to 4 Pig '. . . . 9to 16 2to 13 3to 8 " Horse - .. 9to 12 7to 8 2to 9 Cow .... 4 to. 10 2to 4 Ito 2 Cereal litter .. 6to 20 4to 7 11 to 24 Leguminous litter 27 to 45 7 to- 9 13 to 40 Leaf compost- 18 to 30 4to 7 . 4to 9

Nitrogen is mainly concerned in the vegetative growth of .the plant. It' promotes larger leafage, the rapid extension of growth, and the setting of ' fruit. .It is usually in shortest supply, in early spring, when it is needed in greatest supply by the plant. If present in excess it tends to promote rank, coarse, sappy growth, a weak, constitution,, and susceptibility to disease attack, and it - also has a detrimental effect on the keeping quality of fruit. Nitrogen deficiency is associated with a stunting of growth, yellowish-green leaves, early" defoliation, and poor fruit setting. Phosphates greatly stimulate root activity, which hastens ’ plant growth, particularly in the early, stages. They assist fruit bud and grain formation. Phosphate deficiency is • associated with stunting of the . root shoots, dull green leaves ' with a bronze effect, and often imperfectly-developed blossom. Potash is needed for the efficiency of the leaf and to assist in carbohydrate formation. It counteracts the ill effects of nitrogen excess and produces a sturdier. plant better able to resist disease. It also produces a finer texture in fruit, promotes the development of colour, and improves its keeping quality. A deficiency is associated with leaves of a dull colour. Fruit trees suffering from potash deficiency show leaf scorch and early defoliation. It is sound practice to use complete fertilisers is those containing nitrogen, phosphorus, and potassium— preference to a fertiliser containing but one of the elements. It is not possible to make manurial recommendations which will be applicable under all circumstances, but the following may be taken as a guide for the average tree: — , RICH AVERAGE POOR SOILS SOILS SOILS lb. lb. ■ lb. Apples, Pears, Apricots Sulphate of ammonia ' I ~ I'/a Superphosphate .. 2 : 2 2'/ Blood and bone ;. 22 2'/ ' Sulphate of potash I I / 2 Total 5 6 7 Peaches, Plums, and Sub-tropical Fruits Sulphate of ammonia V2 ', f/2 2 Superphosphate .. l>/ l>/ 2 2 Blood and bone .. 22 2/2 Sulphate of potash I I '/ . Total 5 6 7 Citrus j Sulphate of ammonia I l'/ 2 Superphosphate .. \/ IJ/ 2 2 Blood and hone . l'/ 2 2'/ Sulphate of potash I I . 1/2 .Total 5 6 . 7 Applications of the mixtures recommended may be increased up to 151 b. a tree according to size and cropping capacity. For berry fruits the rate of application- should range between 4 and Boz. a bush, with the same amount to each yard of strawberry row.

Only one fertiliser in each group has been quoted, but they may be replaced by others from the same group. It has been fairly well established that the majority of plants take up the greater' portion of their food requirements, or nutritional elements,' from the soil during the early part of the growing ' season. It is considered that the most active period of nutrient uptake in fruit trees occurs between early root activity and the setting of the crop. That rapid uptake, especially of phosphates and potash, necessitates the application of these elements sufficiently early to 'enable - them to become available at the required time in spring. As they do not readily leach from the soil they may be applied, before spring, and as they tend to -become- fixed in the soil at point of distribution they should be placed as near the root area as possible. It is good practice to - apply, and turn under fertilisers containing phosphates and potash during the late autumn ploughing or digging. ... - . The period of nitrogen application is governed to some extent >by the form in which it-is used, but generally it should not be applied until growth is active because of the likelihood of loss in drainage. As it is soluble and quickly permeates the soil it may be spread as a topdressing and lightly harrowed or hoed. in. Lime . Calcium, the main element found in lime, is an important plant food. Applications of lime decrease the loss of available potash from the soil and assist in the liberation of unavailable potash. Lime has been found of advantage in preserving the availability of phosphates. It is also a corrective of soil acidity and prevents the loss of nitrates. Agricultural ground limestone (calcium carbonate) . may be applied annually in late autumn at the rate of Boz. a square yard. Hydrated lime (calcium hydroxide) is quicker acting and more satisfactory for small home orchards and may be applied at the rate of 6oz.' a square yard. Burnt lime (calcium oxide) may be used on heavy soils at the rate of 4oz. a square yard in the spring, but it is not x recommended for light soils. ? . ■ - Pruning " / Pruning is the art of modifying the natural habit of the fruit tree to improve its commercial value as a cropping unit by securing more regular and prolific crops of good-quality fruit. The main objects of the pruner may be stated as:— 1. The treatment .of the young tree in a manner which will build up a vigorous, , mechanically-strong framework capable of carrying

< heavy crops over a long period without damage; - , 2., To train the tree to a , form which ' i lends itself to ease and economy of ; management, disease control,, and harvesting;. , ’ ' . 3. To provide for an'even, distribution ' of healthy fruiting ■ wood throughout the tree during its fruiting life; 4. To remove dead, dying, and diseased wood; and . • , ; 5. To maintain size and quality of the - fruit. - ; .- .... .... ... Definition of Tree Parts: (Fig. 20): Above ground: Trunk, leaders, fruiting arms, laterals, fruit twigs, wood shoots fruit spurs, fruit, buds, leaf buds. . Below , ground: Main ■ root, 1 secondary roots, lateral roots, fibrous roots, hair roots. . ' - I . Classification of Tree Parts (Fig. 21): — Permanent ' parts (framework): Trunk, leaders, and fruiting arms. Temporary (fruiting) parts: Wood shoots, laterals, fruit twigs, and fruit spurs. ’’ . Pip Fruits Pip fruit trees should be pruned during the winter. For the first five or six years the primary object, of . pruning should be to 'produce a sturdy framework, and during ' those early years fruiting should be allowed only to an extent that . does not interfere with necessary growth. . - • After the tree has been planted, two or three , well-spaced, upright,. sturdy shoots should be selected as the start of the future framework and all other growths cut away. The selected,shoots,, or leaders as they, then become, should; be shortened, about three-quarters of the previous season’s growth being cut off (Fig. 22). The pruning should 1 be back to suitable side buds, so, that the following season two healthy, wellplaced shoots should spring from each leader. At the second winter pruning about five of the best-placed and. strongest leading shoots should' be selected. and the balance cut away. The remaining shoots, or leaders, should be shortened back to about one-third of their new growth and pruned to outside buds to increase the spread of, the tree.

? The ultimate aim should be .to secure a tree with about , six or seven well-spaced, strong leaders, each carrying one sturdy fruiting, arm; the erectness of the leaders is important for strength. Fig. 25 shows a young tree which is unbalanced because faulty pruning in , the early stage has allowed one strong leader to dominate the rest, of the tree. The erectness of this leader has " caused it to outgrow the others. ' . If the tree has made good growth a start may be made at the-.third winter pruning to form 1 the fruiting arms. Having selected the strongest and best-placed shoots for the leaders,

all other competing shoots should be cut right back and only a few of the lighter twigs on the older wood left as laterals. To secure a well-placed fruiting arm, a bud on the outside of each leading shoot is selected about half-way up the shoot, which is then pruned back to the first bud above ,on the inside of the shoot. The effect of this pruning should be to give a strong, erect, leading shoot and a slightly-weaker fruiting arm shoot growing at an angle from the selected bud on the outside of the leader (Fig. 27). Both the leading and fruiting arm shoots are , shortened by half their

length ,to an l outside bud at the fourth winter pruning. A common mistake in training a tree is .to . have too many leaders and too great a spread of the tree, with the result that the leaders tend to be. weak and spindly and unable -to z - stand up under the weight of the ■ crop. The diagram of half a tree in - Fig. 26 illustrates the disadvantages of having too many leaders, which may A be summarised as follows: '/ ; 1. With many leaders each tends to be weak. Frequent breakages of leaders are likely to occur under the weight of : the crop, and propping is required. 2. To lessen the overcrowding, leaders . are usually brought out at an angle, which increases the weakness of the limb and its likelihood to bend and break under the weight of the crop. 3. As the leaders bend outward under the weight of successive 'crops the fruiting wood tends to become established inside the ring of leaders, which makes both disease control and harvesting more difficult. 4. Too many leaders preclude the development : and extension of

laterals because of overcrowding, ... and . therefore . necessitate , dependence on the spur system of fruiting. 5. Overcrowding causes shading of , fruit and poorer colour, tends ,to prevent effective spray penetration and coverage, and leads to inadequate protection against insect and disease attack. ' 6. Spreading leaders increase difficulty of cultivation close to the : tree. - The advantages of the modern, erect type of tree having few leaders are illustrated in the diagram of two leaders shown in Fig. 24, and may be summarised as follows: \ 1. Upright leaders mean strength. 2. A limited number of leaders secures greater weight in each leader, with i greater ability to' stand up under the weight of the crop. 3. Leaders well , spaced enable full development of desirable lateral growth. 4. Development of one sturdy fruiting . arm to each leader . increases the fruiting area within easy reach. 5. Sturdy leaders and fruiting arms do not require propping, and fruiting arms are up out of the way of cultivating equipment. - - 6. Fruit is produced , outside the ring of leaders and so secures maximum ~ air and sunlight,, spray penetration' and coverage are facilitated, and the - fruit is. more easily picked. As the tree becomes older the leaders and fruiting arms become furnished with. laterals, twigs, and

spurs, which constitute the fruiting parts of the tree. While the spurs and laterals are young and vigorous they carry excellent fruit, but as they age and weaken they become poor conductors of plant food and fruit carried on them is likely to be small and of poor quality. It would therefore appear. reasonable that the old and exhausted wood should be cut away and young, vigorous wood encouraged in its place, but unfortunately the opposite appears to be the rule in the average home orchard, and the old wood is carefully preserved year after year. ' . . The system of pruning recommended envisages the continual removal of fruiting wood as it becomes exhausted and the refurnishing ' of the tree with young, healthy laterals and twigs. Laterals are encouraged in preference to spurs, as they are better, conductors of plant food. and are more easily renewed when they become aged. : In the treatment of the bearing tree the temporary parts are divided into three classes (Fig. 23): — 3. Old and exhausted fruiting wood; each winter the greater part of this spent wood is cut away to promote new growth. . 2. The present healthy fruiting wood, which is . shortened where necessary to preserve its vitality or to prevent overcrowding. . 1. The future fruiting wood or new growth, which is thinned out where necessary to prevent overcrowding, those remaining being left unshortened for the first year; that has the effect of causing them to develop fruit buds along their length the following year. The cutting or shortening of all annual wood shoots is likely to cause

excessive growth and is also detrimental because 'of the, removal of much valuable early leafage which is required to assist fruit setting. ■ The purpose of the temporary wood is fruiting, and greater and ' earlier fruit bud formation is encouraged by leaving the new lateral growths and shoots unshortened for the first year. Fig. 29 shows the fruit bud development on unpruned laterals of Graven stein, Sturmer, and Jonathan. In brief, the lateral shoot is grown, encouraged to fruit early, and after a short fruiting life is cut back and renewed; the cycle then begins again. Fig. 28 illustrates the cycle of refurnishing for apples and pears. A rationalised. system of refurnishing will keep the tree sufficiently vigorous without ■ causing excessive growth. Should a tree be too vigorous, less new growth should be thinned out; conversely, as the tree-becomes stagnated more cutting back ,of old wood is necessary to promote increased growth. .. • \ ■ Old trees which have become stagnated and devoid of new extension growth may be rejuvenated by that method of refurnishing. 1 For the first winter treatment of such trees 30 to 40 per cent, of the exhausted wood should be cut away to promote new growth. The balance of old spurs and

laterals, should be cut' back and renewed during the ' following three to four years, and the normal cycle of refurnishing over a five- to six-year period then followed. 1 Stone Fruit The training of a young stone fruit tree broadly follows the outline given for pip fruits. It is essential that a sturdy framework be built up while the tree is young. Peaches, nectarines, and plums are usually 'more vigorous in growth than pip fruits, and the building of a sturdy framework presents much less difficulty. After the planting of the young tree, three or four strong shoots should be selected as the basis of the framework and all others cut away. The selected shoots should be pruned back to outside buds, about three-quarters of their length being removed. Frequently, because of faulty treatment in the nursery, trees are received which present a problem to the buyer when he ; comes to prune them after planting. .. It is essential that the growth be started on sound lines, and if the placement of the main shoots is unsatisfactory, or the growth too uneven for use to be made of the required number of shoots in the first year, it: may be necessary to select only two or, in extreme cases, to discard all and cut back to a single rod. Fig. 36 shows a well-shaped tree as secured from the nursery and the right treatment at pruning. From five to seven : leaders are sufficient, and in districts where very strong growth is made by peaches, nectarines, and plums the framework

may be built rapidly by leaving the leaders unshortened for three or four years after the second or third winter pruning. However, though the annual extension growth of the leader may be left unshortened, most light laterals on this growth should be cut. right back for, the first year. Apricot and cherry trees . are seldom as stronggrowing as peaches and plums,., and their framework should be built by annual pruning. Fruiting arms should be developed on the outside of the leaders as for pip fruits. The treatment of the bearing tree once the, framework has been established satisfactorily varies according to the fruiting habit of that kind of stone fruit. • Peaches and nectarines fruit only on lateral growth made the previous season, and pruning consists of the removal of the ‘ two-year-old laterals to induce new growth and the thinning out of the one-year-old wood where necessary to prevent overcrowding. At times the whole of the light lateral wood along a fruiting arm or heavy lateral may be one-year-old, and if left

without thinning, the whole .of it becomes two-year-old and ’needs to be cut away at the next winter pruning. The correct treatment would be to thin out, half of this wood the first year ■ and leave half for fruiting; the following winter' the laterals left for fruiting should be cut outand the new ones which have grown should be left for fruiting. These fruits require a heavy annual pruning, and usually it is necessary to cut back more than half of the lateral 1 growth at each pruning. Fig’ 37 shows lateral growth of a peach before 'and; after pruning. Failure to cut. away sufficient lateral growth results in the lower parts of the tree, becoming devoid of fruiting wood and all the new growth being at the top of the tree; should that happen, the leaders should be short--ened sufficiently to cause new growth to break out; lower down and so refurnish the tree. Plums, apricots, and cherries fruit mainly on spurs of two years and older. Refurnishing should be carried out over three to four years by cutting back 25 to 30 ' per cent, of the older spurs and laterals each year. As with pip fruits, robust fruiting laterals are 'to be preferred to spurs, * which soon become weakly and carry poor-quality fruit. Vigor-ously-growing plums are often left unpruned and eventually become a tangled mass of growth. Fig. 38 shows part of an unpruned tree and z the necessary thinning out.

Citrus Fruits The belief that citrus trees do not require pruning is fairly common. The result has been the decline of many trees soon after reaching maturity because of overcrowding of fruiting wood and borer obtaining a hold. Though it is seldom necessary . to prune citrus trees as heavily as pip and stone fruits, a moderate pruning should be carried out each year to admit sufficient light and air for the proper development of shoots, buds' and fruit. During the first few years a strong framework should be built up. A little more care and attention is required in the building up of a strong citrus tree with well-placed leaders than with pip and stone fruits, but, if only strong shoots are selected for the leaders and all weak and unsatisfactory ones are cut away for the first two or three years, a satisfactory framework can be achieved. Lemons'should be kept more open than oranges or grapefruit, but even they should not be as dense as is common. When the framework has been built and the tree has begun regular fruiting, the pruning consists mainly of thinning out crossing laterals, all dead, dying, and diseased wood, and any heavy, upright water shoots. Most lemons are pruned in the spring when the. danger of ‘ frosts is over, but the pruning of oranges is usually delayed until the fruit has been harvested.

. Where little pruning has been done in the past it is probable that a citrus tree will have become very dense and a fairly-heavy, thinning out of branches and surplus leaders will be necessary. In such instances it is preferable that the work be spread over two or three ■years, it being sufficient in the first year to remove a few of the more (central vertical branches and , any ■crossing laterals. ■ , Other Sub-tropical Fruits • Passion fruit vines are usually very little pruned by the home gardener, and before very long they become a ■tangled mass subject to disease attack, which frequently causes the death of the vines at an early age. The vine bears its fruit on the current season’s > growth, and if left unpruned, . the fruiting surface becomes further and I further removed from the main leading growths. The vine should be trained along or over some suitable i trellis by selecting four or five of the strongest shoots to form the main leading growths, or vines. The number of vines to establish will depend on whether the plant .is being trained along a fence — which case five or six are sufficient— over a wide rather than long areain which case nine or ten main vines may be retained. When a framework of several main vines has been formed the annual pruning, usually carried out in early spring, consists of cutting the lateral growths back to the second bud from the main vine. Keep the plant as open as possible and, with the exception of the main vines, constantly prune

off the laterals to a bud at the base. At first this pruning may appear rather drastic, but once it is realised that the fruit is carried only on the growth of the current season, the system of laying down sufficient main vines and keeping the lateral growth pruned back to these vines each spring can readily be appreciated. From time to time the main vines should be re-

newed by laying down a new growth coming from well back on the old vine and then shortening the vine back to the growth selected. - Chinese gooseberries, like passion fruit, if left unpruned, soon become an uncontrolled, tangled mass of growth, and the fruit rapidly decreases in size. As these plants are usually extremely vigorous, sufficient room ; must be available to train the vines along or over a strong trellis. Unless adequate room is given, keeping the vine within bounds will be extremely difficult. In many ways the growth and fruiting habit of the Chinese gooseberry 'resemble those of the grapevine. A satisfactory method of training the vine is along a fence. Several main vines should be trained along the wires on either side of the main stem. From these main vines strong one-year-old laterals will develop, and in the winter a number should be , retained and the balance cut back to the main vines. Those re-, tained should be shortened to between 4 and 6ft. . and tied down in a sort of bow shape. The fruit develops on current season’s growths from the first four or five basal buds on these laterals, and where growth is vigorous it is advisable to stop it at a point several leaves beyond the last fruit. All growths ‘ from the tied-down laterals, whether they have carried fruit or not, should be shortened back , to about a length of four buds for fruiting the following year. Laterals

should be renewed every two or three years by laying down a few new laterals each year. Unless the vine is pruned annually .and the ' fruiting wood renewed, the vine. will increase the quantity of fruit,to the detriment of size and quality. Fig. 39 shows a badly-trained vine and Fig. 40 pruning being completed on a well-trained vine. . ■ Tree tomatoes lake very, vigorous growth, especially during the first few years of establishment The young seedling rod should be pruned at from 3 to. 4ft. from' ground level to encourage the development of three or four sturdy leaders. Plants raised, from cuttings are relatively short and bushy, and frequently the removal of some of the lowest branches, which may be resting on the ground, becomes necessary. . Having produced a strong framework v of several branches, pruning of the fruiting plant consists mainly of the removal of lateral wood: As the tree tomato fruits on wood of the current season,, all laterals which have fruited should be shortened back to the main limbs and heavy lateral growth. The annual extension growths of ' the limbs should be severely shortened once the framework has been built. Heavy annual pruning is necessary to maintain size in the fruit. Berry Fruits Raspberries bear the current season’s fruit on the canes ’produced 1 the previous season. Pruning consists of the removal at ground level of all’ canes which have cropped during the season, together with any weakly or diseased ones of the current season’s growth. From 6 to 8 canes are usually sufficient to leave to carry the crop. Though it is the general practice to begin pruning -in the late autumn, it is recommended (except for the Lloyd George variety) that pruning be carried out as soon as the fruit has been harvested. The canes selected to carry the next season’s crop will then be fully exposed to the sunshine, which will assist in the ripening of the canes.

Gooseberries carry their fruit on the one-year laterals and spurs from older branches. The aim of pruning is the establishment of a sturdy framework of several branches and the provision of well-placed lateral growth for fruiting. Fruit buds on new growth are preferable to those on old spurs, and the bushes should be refurnished every two years. They should be kept open, and all crossing laterals and those likely to rest on the ground should be cut away. - The weeping type of plant, such as Farmer’s Glory, should have the main / shoots pruned to inside buds to make them more erect. - • , Black and Red Currants The black currant fruits chiefly and produces the majority of • its most luscious fruits on the growth made the previous season, whereas the red currant fruits on the two- and three-year-old wood and on spurs from older branches. • ' > ' ' The pruning of black currants consists of removing branches which have

fruited and leaving strong young wood for fruit production. The old wood should be cut back to strong, healthy young shoots, the nearer to ground level the better, as it is desirable to remove.as much of the old wood as possible. Some bushes . may produce new wood from the butts below ground and this may be retained for fruiting. Keep the bushes well spaced and open -to prevent overcrowding. The plants should be kept sufficiently vigorous to produce ample strong new growth each season. It is of advantage to carry out the pruning immediately after the crop has been harvested. . The red currant requires different treatment . from the black currant. It is pruned to form a bush of eight to 12 sturdy branches ; arid the fruiting laterals and spurs are renewed every four to five years as the fruiting spurs begin to become sparse on any piece of older wood. The bush should be maintained in sufficiently vigorous condition to develop at least four or five. new vigorous shoots annually. .. Treatment of Tree Wounds Tree wounds, whether caused accidentally or through the removal at pruning time of fairly large branches, must receive proper attention to prevent bacteria - or the spores of fungi gaining entrance through exposed tissue. After . pruning*. all cuts larger than Jin. in diameter should have the edges carefully trimmed with a sharp knife (Fig. 41) and a tree-sealing compound, such as bituminous paint, applied over the cut. Tar should not be used. Fig. 42 shows . a stub left through a cut being, made at' the wrong position; the cut should have been closer to the main branch as in Fig. 41.' ■ All photographs in this article by Sparrow Industrial Pictures Ltd. .

The first article of this series, published last month, dealt with ; the establishment of a home orchard. In, this article cultivation, pruning, and other details of , general maintenance are discussed, and next month measures to control pests and diseases will be detailed. < ,