Horticultural Instruction.

New Zealand Journal of Agriculture, Volume 56, Issue 5, 20 May 1938, Page 363

Horticultural Instruction.

Contributed by Officers of the Horticultural Division.

Pruning Operations in the Orchard.

TTT rITH the advent of the winter WITH the advent of will be conseason fruitgrowers will be considering . pruning in order to complete the work while the trees are in a dormant state. A fairly early start is advised, as weather conditions cannot be relied upon at this season of the year, and often, many growers have not completed pruning operations before growth commences in the spring. This means rushing the job through before the spraying season starts, with the result that the trees are, in many ,cases, improperly pruned. ' - The usual practice is to prune the different - classes of fruit as they lose their foliage, and consequently stone-fruits are the first to be operated on. The work of pruning requires much skill and attention, and should not be hurried if the best results are to be obtained. A successful pruner should possess a good knowledge of the basic principles governing the development and maintenance of a healthy tree capable of producing good average growth every season, and of the necessary fruiting wood on which to carry an annual. crop of high-class fruit. No detailed system of pruning can be given which would be applicable to all districts and under all conditions, but providing the pruner keeps the main objects in view he will not go far wrong, and any other details to suit local conditions can be easily supplied. Stone-fruits. Peaches and Nectarines. ■ As the growth and fruiting . habits of the peach and nectarine are similar the same style of pruning is applicable to both. These trees produce their fruit on the previous season’s growth, and in order to obtain the maximum results a full supply, of young wood and spurs on .the lateral growth is essential. -. This can best

be 'obtained by a judicious thinning out during the pruning season and by suppressing many of the stronger laterals entirely in order to induce further development of new growth in the following year. With .regard to the shorter and weaker one-year-old laterals, the usual practice is to leave these entirely, unless too crowded, allowing them to fruit the following season, and then to remove them. , Peach and nectarine trees usually come into bearing at an early age. Therefore when training a newly planted tree the aim should be to provide it with strong leaders capable of producing good fruiting branches which, in turn, will be able to carry average crops of fruit for many years. The number of leaders required to form the tree depends largely on the type of soil in which the tree is planted. It should be' remembered that, with the usual vigorous growth during the first few years and the heavy foliage produced, a tree with too many leaders is apt to become overcrowded and produce wood which is more or less sappy and immature, to the detriment of fruiting. Excessive growth also prevents the sun from penetrating to the inside of the tree, ■ delaying maturity and the production of good-coloured fruit. - Spraying operations are also handicapped. Judicious Cutting. The position of the chosen leaders should be maintained throughout the lifetime of the tree. This can best be done by judicious • cutting every year, the length of cuts depending largely, on the growth made during the previous summer. Some pruners are apt -to be too severe on the leader-cutting, while others leave them -uncut and shorten back all laterals appearing on the current season’s leader growth.

Best results ’ appear to be obtained by a medium cut of the leaders, the cuttingback or complete suppression of the competing heavy laterals, and the leaving intact of any small lateral growth for fruit-production the following year. By this means the tree will soon become furnished with healthy growth and fruit-ing-wood from top to bottom. On no account allow the . top of the tree to become overcrowded with growth, or the laterals and fruiting wood in the lower parts of the tree will soon die out, leaving the bare limbs which are so conspicuous in some orchards. Pruning for fruit in peaches and nectarines is- a series of replacements, cutting out every season two-year laterals that have fruited and leaving the one-year-old laterals to carry on. These in turn will be cut away to make room for further short laterals. A number of spurs and laterals die every year. These should be removed, or bare branches will be the result. Summarizing the foregoing advice, the main objects in successfully pruning a peach or nectarine tree are to build up a fairly open tree with a moderate number of leaders, to maintain good, average growth every season by judicious cutting of the leaders, to cut back or remove entirely laterals as they become unfruitful, and to maintain sufficient fruiting wood for the production of . a good, average crop of well-coloured fruit. Apricots. Like the peach, and nectarine, the apricot, if planted in a suitable . soil and situation, is a strong grower during the first few years and until it has settled down to fruiting. For the first three or four years fairly heavy cutting should be given to ensure the development of a strong framework, - after which pruning

can be considerably modified as far as leaders are concerned. Apricot trees, if well cared for, should come into bearing the fourth year after planting,- the majority of the fruit being borne on short spurs which develop-all along the main leaders and heavier laterals. Long and heavy lateral growth should be shortened to within a few buds of the base every season. This will materially assist in the formation of fruit buds and spurs, upon which the best fruit is grown. Short. laterals and fruit spurs need not be touched until after bearing, when they should be cut. back to make room for a further supply of fruiting wood. As with the peach and nectarine, the pruning of the apricot, especially after reaching maturity, consists mainly of the removal and renewal of fruiting wood and the maintenance of sufficient vigour to produce crops of fruit. . As the tree ages and bears heavy crops, top or leader growth will slacken off and in some cases cease altogether. It will then be necessary to prune heavier to encourage new growth, without which no fruiting laterals or spurs can be fully developed. Cherries. After the trees are formed and well established very little pruning is required in the average cherry-tree. Even with the formation of the tree it is not advisable to cut as hard as with other stonefruits. The cherry-tree is very subject to "gumming,” and heavy cutting accentuates the trouble. The majority of the fruit is carried on spurs from 1 in. to 3 in. long. These spurs are produced on two-, three-, and four-year-old wood, and will continue to develop almost to the ends of the branches. Unlike the spurs on the peach and nectarine, they are long-lived, and will continue to carry fruit for several years. In the centre of the cluster of fruit spurs there' is usually a wood spur, which, as it extends each season, will burst into blossom and carry a crop of fruit. The aim of the pruner should be to develop as many of these spurs as possible, allowing them to produce fruit until ■ they become old and knotted, after which a judicious thinning out and renewal is advised. In fact, it always pays to treat a good number-of these spurs every year, cutting out the older ones to make room for a new supply of young, fresh wood. ■ The cutting-out of any large limbs, cross branches, &c., should be done during the summer after the crop has been harvested. It is found that wounds heal more rapidly at this time, and there is also much less danger of “ gumming.” All wounds should be well covered with a coating of white-lead.

Plums. The majority of plum-trees, both European and Japanese, are strong growers when young. Consequently, after the tree has been shaped by fairly heavy cutting of the leaders it will not be necessary to cut so hard, more attention being given to the fruiting habits. On European plums the majority of the fruit is borne on laterals and spurs of two years and older, while ' on Japanese varieties the fruit is carried on spurs and laterals of the previous season as well as on older wood, Japanese plums are

usually more e prolific bearers than the European varieties. . The system of pruning consists mainly of the elimination of old worn-out laterals-and spurs, replacing them with young fruiting wood. When pruning, not only should the clusters of spurs be well thinned out, but laterals not required for fruiting should be removed at. the base. Laterals and spurs required for fruiting should not be touched until the next pruning season. , -7— George Stratford, Orchard Instructor, - : Motueka. ■

Citrus Culture.

GOOD drainage is essential to. successful citrus ’ culture . and must therefore receive full consideration both in the establishment of new orchards and in the maintenance of existing ones. Insufficient drainage frequently results in the development of serious barkdiseases, such as collar-rot, bark-blotch, &c. . Good drainage greatly assists in the improvement of the fertility of the soil, and most orchard areas are improved by additional drainage. Drains should be large enough and have sufficient fall to carry away the water quickly when heavy rains are experienced, and should be about 3 ft. or more below the surface. For a few years after planting, citrus trees'will, under certain conditions, make good growth where the winter water-level is about 2 ft. below the surface. This fact is liable to give growers a.feeling of false security, for as the tree matures the roots penetrate to a greater depth, and consequently a lower waterlevel becomes essential for the maintenance of healthy trees. Shelter. Adequate shelter from all winds is probably more important with citrus than any other kind of fruit-trees grown commercially in New Zealand. Young trees checked in growth for several seasons by exposure to winds seldom make satisfactory growth afterwards. Consequently,

in establishing a young orchard it is best to delay planting for one or two years rather than set out trees in exposed positions. Good, permanent shelter-belts around the boundary should be established at least two years before planting young orchards.

Among the kind of trees that may be. used for such shelter might be mentioned Cupressus Lawsoniana, C. macrocarpa, or C. Benthamii, Pinus insignis, Eucalyptus amygdalina, and Lombardy poplar. All these trees are not suitable for all conditions. For instance, in areas where a relatively heavy summer rainfall , is experienced and drainage is bad C. Lawsoniana is not proving satisfactory ; likewise, the Lombardy poplar is unsuited to well-drained, light, pumice soils. In districts where Hakea saligna flourishes this tree provides an excellent shelter about io ft. to 15 ft. high and sometimes even higher. However, shelter of a greater height is usually desirable for mature trees. Hakea saligna is at times employed most successfully in combination with taller-growing trees, especially where the latter . are inclined to become bare of foliage near ground level. The possible disadvantage of this tree is that it may prove to be a host for borers which attack citrus. In cases where the permanent shelter has not yet reached sufficient height to provide adequate protection it is advisable to subdivide the orchard into smaller blocks by planting a quick-growing temporary shelter. . For • this purpose Albizzia lophantha is generally suitable, and has been known to grow to a height of more than 6 ft. from seed in the first

year. The seed should be sown | in. deep in the position where the trees are to grow. For quick germination place the seed in a bucket and cover it with water which is boiling hot ; leave the seed in

the water for ten to twelve hours, and then pour the contents ■ of the bucket into a fine-meshed riddle. Mix the seed with a little dry sand to separate it, and sow as soon as possible. The seed should not be allowed to dry after soaking. Brown-rot. . ' Prevention is preferable to a hurried attempt to effect a cure when applied to citrus brown-rot (Pythiacystis citrophthora}. Where Bordeaux mixture

3-4-50 has ■ not recently been applied for this purpose the application should be made without further delay. Further remarks on the control of this disease appear in these notes for the previous month.

•.. Packing. • In view of- the recently introduced compulsory grading regulations it is expected that more than usual interest will be taken by growers in the art of packing. Lemons are packed in much the same manner as are apples, except that .the 3-2, 7-6, five-layer pack (163) is replaced by the 3-3, 5-4, six-layer pack (162). The following packing chart will accommodate all sizes allowed to be marketed (other than to a factory) under the. New-Zealand-grown Fruit Regula-

tions 1938. Sizes which pack 252 to 319 inclusive may be sold only as “ Small Grade.”

Sweet oranges are packed in the same manner as are apples. The method of packing New Zealand grapefruit differs from that used for other fruits in that it is usually packed on the flat. As this method gives different counts from those obtained in packing in the ordinary way a chart for use with the standard bushel case, for New Zealand grapefruit and marmalade oranges only, is given below :

—Percy Everett, Orchard Instructor, Gisborne.

Viticulture.

The Vinery. IN vineries where late varieties are grown for the purpose of offering for sale, when the bulk of the outdoorgrown grapes are off the market, it is of considerable importance to keep • the hanging ripe grapes in attractive marketable condition. To obtain this end the bunches should be shaded from strong light. Where the foliage is not thick enough, or where the leaves have fallen, brown paper shades can be placed over individual bunches, or the glass can be covered with whitewash. Ventilation should be given freely on hot, dry days, and under cold, damp conditions a little

artificial heat should be supplied. Damping-down on fine, bright mornings to keep the berries from shrivelling is very seldom called for under the climatic conditions prevalent in New Zealand in autumn. A decayed berry in a bunch is liable to spread its condition, and can easily ruin an otherwise fine specimen bunch, to avoid which frequent inspections are necessary. Ripe bunches of grapes of some varieties such as the Black Hamburg and Golden Chasselas —the variety known in New Zealand as Albany Surprise is unsuitable—can be kept for a few months in cool

storage under the same conditions as other fruit. Another method of keeping grapes is to cut them' with a sufficient length of lateral to go into a wine or whisky bottle nearly full of water. A few pieces of charcoal are placed in the bottle to keep the water sweet. Care should be taken to avoid overfilling the bottles when drips of water from them might cause the bunches to rot. The bottles are placed on inclined shelves so that the bunches hang free from contact with the bottles or shelves. The ideal store is a dry, dark room or cupboard in which the damp can be overcome by heating or by placing a tin of freshly burnt, lime in it.

The Vineyard. The wine grapes having . been turned into wine and the table grapes marketed, the next major operation will be pruning. In the meantime there are many jobs which can be carried out, Such as digging out vines to be replaced, pruning surface roots off young vines, putting in posts for trellising after pruning. Land now under grass intended for the planting of vines can be skim-ploughed as soon as it is in suitable condition and the sods allowed to rot on the surface to be followed in the early spring by a deep ploughing across in the direction of the skim furrows. Cellar. In the new wines a slow fermentation will continue in the dry wine for a month or two, and in the sweet wine much longer, the exact period' depending principally on the amount of sugar present. Gas will be produced as long as fermentation continues, and might cause the container to burst if it is tightly bunged. A good plan is to cover , the bung-hole with a small bag of clean sand laid over a vine-leaf. This will keep out the air and flies and at the same time allow the gas to escape. . When used to cover the bungholes of the barrels of fermenting dry wines or cider, these bags retain in the barrel some of the gas . formed in the process of fermentation, and at the same time keep out the air, a condition unfavourable to the development of the dreaded vinegar bacteria. The barrel should be bunged tightly when the sizzling noise produced by the escaping gas-bubbles ceases. At this period, when the wine has become fairly clear, it should be racked or separated from the lees. This can be accomplished by inserting a wooden tap in the barrel above the lees or by siphoning the wine out with a rubber tube tied to a piece of cane so that the end of the. tube will be a few inches from .the end of the cane and above the lees in the container. Dry wine is usually racked after fermentation, and at the end of the winter, twice during

the following twelve months, and once or twice in subsequent, years, whenever possible choosing cold, bright weather to perform the operation. Sweet wine is racked .twice the first year and once

during subsequent years until it is quite clear and bright. . During the maturing-period of dry wines the barrels must be filled up regularly from small vessels kept for the purpose to replace the wine which evaporates through the wood. .If an air-space is left mould is liable to form on the surface of the wine, and will probably cause the wine to turn sour. Air on the suface of sweet wines will not have the same consequence. - —J. C. Woodfin, Vine and Wine Instructor, Te Kauwhata.

The effect of the size of the potato-seed on the size of top is clearly demonstrated at the potato-certification trials in Canterbury this year, tables having produced much bulkier tops than lower grades of the same line. . -

Experiments bn Soya Bean.

EXPERIMENTS carried out on soya beans by Mr. A. F. Bell at Tahunanui, Nelson; have yielded some interesting results. He finds that rich soil is wasted on soya bean, and that a light, loamy soil suits it best. Sunshine, good drainage, and freedom from weeds are essentials. Undried seeds average 1,984 to the pound. Mr. Bell experimented .with two distinct sowings. In the first (A) he planted the rows 3 ft. apart and the seed 3 in. apart, at a depth of 1 in. This sowing was carried out on , 10th November, germinated on 22nd November, and flowered on 9th February. It has not yet matured, but will be ready to harvest about 20th April. The second experimental plot (B) was laid out in rows 3 ft. apart, with the seed 2 in. apart and 2 in. deep. This crop was sown on 16th November, germinated on 25th November, flowered on 26th January, and matured on 25th March. It was noticeable that plot B produced more sturdy plants than plot A, and the majority of pods contained three beans. This may have been caused by planting the seed deeper than in the first. Plants in plot A were inclined to be spindly, and the majority of pods . contained two beans. It is thought that the variation was possibly caused by the depth and space of planting. . Further, . the wind affected rows A more than rows B, and there again surface planting less than 2 in. caused the roots to spread rather than to penetrate downwards. Rows B had slightly more surface than rows A. The plant photographed has 173 pods, but some had more than 200 pods. Row B grew to 48 in., • with moderate foliage, and row A to 60 in. with prolific foliage. Mr. Bell is unable to give the actual name of the variety, but the seed

used was a Manchurian bean. There are thousands of varieties, varying in height from 12 in. to 60 in. . A considerable amount of soya bean is grown for hay in the United States, where it is generally • considered to be equal, or even superior, to red clover or the best lucerne. It is used largely in the feeding of dairy cows and as a winter ration for young cattle., Mr. Bell is convinced that it is a cover crop to restore poor land. A number of tobacco-growers were supplied with seed by Mr. Bell, and some instructive information was gained. In the first experiment the seed was planted only 1 in. deep. The plant grew to a height of 54 in., with plenty of pods and foliage, but the wind was inclined to knock the plant about. The second

experiment was in two rows in a tobacco field. The plants were a long time in flowering, but produced heavy foliage. When the tobacco was harvested the cows were turned in and made straight for the soya beans, and quickly consumed the lot. The third crop was sown on 15th November, germinated on 26th November, and flowered on 26th January. The rabbits then finished the crop. The fourth grower raised a very sturdy plant, bearing 208 pods. He planted three long rows, which were successful, and proposes planting this coming season as a cover crop. The majority of the other reports are similar, although the exceptional season might account for the prolific growth of the bean. '

Price of Raw Tobacco.

A. E. Morrison,

Solicitor, Department of Agriculture.

r I""<HE Board of Trade (Raw Tobacco Price) Regulations (Raw Tobacco Price) Regulations 1938, which came into force on 12th April, 1938, prescribe that no raw tobacco—that is, all unmanufactured tobacco, including the leaves and stems of the tobacco-plant' before they have been passed through any process of manufacturing except curingmay be sold by

or purchased from any grower at a price less than is. 2d. per pound f.o.b. Motueka or Nelson, in the case of tobacco grown in the Nelson Provincial District. In the case of tobacco grown in any other district, nd raw tobacco shall be similarly sold or purchased at a price less than is. 2d. per pound f.o.b. or f.o.r. the

port or railway-station which is nearest to the place at which the tobacco is grown. The Minister of Industries and Commerce, whose Department administers the regulations, may, however, authorize the sale and purchase of tobacco at a price less than the minimum price prescribed in any case where he considers it proper so to do.

Seasonal Tobacco Notes.

r I ’HE harvesting and flue-curing of THE harvesting and now comyellow tobacco leaf is now completed in the Motueka-Nelson district, and the season has been a very good one for the production of good, bright leaf. The growers who have contracted with the tobacco-manufacturers were busy last month grading tobacco to the grades set by the purchasing companies. This line of work has been undertaken much earlier than is usual. This haste is not in the best interests of the tobacco, which is greatly improved by the bulking down process, and should at least have two months in the bulk, where a mild fermentation takes place. The leaf becomes mellow, and the colours are more defined ; shades of green disappear, and elasticity is established, with the gums brought to the surface. The month of April, however, will be the grading month for the majority of the growers. Grading-tables. - - There is room for improvement in the construction of the grading-tables used in the Motueka district. - These are usually made with fixed grade divisions down the centre of a wide table, at which graders work on both sides, putting their selected leaves into the grade space common to all the workers. This method makes the slowness of any individual - worker hard to detect, and incorrect grading cannot be charged to any particular worker.

The most useful table is a hollow square with a i-ft.-wide board surrounding the worker and hinged to the wall, with the overhead light to the south. The leaf to be graded is placed in front of the operator who separates it into adjustable grade divisions on each side. Thus, each worker’s speed and correctness of work are clearly shown. This tends to improvement of the individual, and fosters a competitive spirit ; the indolent and careless worker is quickly detected, and if incapable of improvement can be put to some other class of work. A description of Government export grades of tobacco will be dealt with next month. Seasonal Work. Another phase of seasonal work to be undertaken in the. tobacco-field during April is the removal of the standing plant that has been stripped of its mature leaves, but which is still carrying an abundance of sucker leaves and blossom-heads. These should all be pulled up by the roots, laid straight in - rows to dry, four planted rows being placed in one. When partially dry the leaves should be heaped and sprinkled with a little used engine oil and burned in the field, or removed entirely from the vicinity. A very common practice in this district is to use a motor-tractor with heavy double disks to chop up the residue of a heavy crop of tobacco preparatory to.

ploughing it into the land. Under certain conditions this practice has the advantage of adding organic matter to the soil and is quite all right provided the plant so treated is free from disease, but as almost all of the remaining standing growths are infected with the mosaic disease tobaccogrowers who are . disking and ploughing in this infected material are certainly providing a source of infection for next year’s tobacco-plants. These old plants should be removed, root and branch, and destroyed. —■ C. Lowe, Tobacco Instructor, Motueka.

Cool Storage of Fruit.

X'V’THILE the fruit is coming into the WHILE store care must taken to cool store care must be taken to avoid too much accumulation of carbon dioxide. This condition becomes noticeable again when the store is full and accidental ventilation stops. Blowing out three times a week is advisable at this stage, and is easily attended to . early in the morning by opening packing-shed and chamber doors for ten minutes. The grading-out of the larger sizes of apples should be given attention early, and the placing of these in a position of easy access will save time and loss later in the year. Granny Smith apples should not be placed in the cool store immediately after picking ; they should be placed in a cool, dry position, and the stack well ventilated. They can be held in this way for from three to five weeks, according to state of maturity when picked. The tint or shade of colour will determine their readiness for cool storing. If these directions are followed and the fruit is given a chance to mature fairly well before picking there will be no . losses from immature discoloration, commonly known as " scald.”. The stacking of fruit correctly in the cool chamber is a very important factor in the cooling and air-conditioning of the room.- Plenty of ventilation is necessary to allow the gases to escape freely and the fresh cool air to circulate around each tier of fruit-cases. Vertical ventilation is recommended, but the system of aircirculation is a factor which controls the method of stacking. Direct expansion, ceiling cooling, gives the best out-turn and is coming into general use. All waste fruit should be removed from cool-storage premises daily. —A. Powell, Cool Storage Officer, Wellington.

Style of Number in Number of Size Pack Rows Layers or (Crosswise). Number in Rows (Lengthwise). Number of Layers (Depth). Size or Count. 3-2 5-5 5 ' 125 3-2 6-5 5 138 3-2 6-6 5 150 3-3 5-4 6 162 3-3 5-5 6 180 3-3 6-5 6 198 3-3 6-6 ■ 6 216 3-3 7-6 6 234 3-3 7-7 6 252 3-3 • • 8-7 6 . 270 3-3 8-8 6 288 4-3 6-6 . 7 ' 294 4-3 7-6 7 319

, Style of Pack (Crosswise). Number in Rows (Length- ■ wise). Number of , Layers (Depth). Size or Count. Approximate Diameter (Inches.) 2-1 3-3 5 45 41 2-2 ' . 3-2 5. 50 4 4 2-2 3-3 5 , 6o ' 31 2-2 . . 4-3 5 70 31 2-2 4-4 5 80 3s 2-2 5-4 5 90 3«o— . . 5-5 5 100 ‘ 31 3-3 ' 4-3 6 -105 31 ' 3-2 ■ • • 4-4 6 120 31 3-2 5-4 • 6 135 3 3-2 5-5 6 •150 2? 3-2 6-5 6 165 2? ( 3-2 6-6 6 ■' 180 2f