THE ORCHARD.

New Zealand Journal of Agriculture, Volume 54, Issue 1, 20 January 1937, Page 53

THE ORCHARD.

Seasonal Spraying.

Many growers throughout the Dominion make a very serious mistake by discontinuing spray applications many weeks too soon. Presumably this is done for economic reasons, it being considered that the cost of spraying towards the latter part of summer and early autumn is not warranted. This view, however, is a “ penny-wise and pound-foolish ”, one. The discontinuing of spray applications too early in the season inevitably results in a far greater percentage of rejected fruit during the process of grading. The result of a few insect stings, injury of leaf-roller caterpillar, or pinhead black spot, individually or collectively, is all that is required to reduce -otherwise extra fancy fruit to the reject class. In view of these circumstances it is recommended that pip-fruits be sprayed as recommended in the November notes, for the control of black spot, leaf-roller caterpillar, and codling moth. If red mite is still prevalent it will be necessary to spray with summer-oil 1--80. In order to reduce spray residue, early varieties of apples, such as 'Gravenstein, which are intended .for export, should not be sprayed later dhan fourteen days previous to picking. Stone-fruits should still receive attention by periodical applications of ■the sprays recommended in last month’s notes. Harvesting the Crop. The importance of care in the preparation of fruit for either local or -export markets cannot be emphasized too strongly, as considerable losses .accrue through faulty handling during the picking, grading, and packing ■operations. The packing of the crop calls for considerable discretion and care on the part of the picker. Carefully picking to size and. eliminating the obvious ■culls greatly facilitate the work in the packing-shed. Rejected and .fallen fruit should not be allowed to remain on the ground, but should be gathered, .and if not utilized should either be buried deeply or burned. Attention should also be paid to maturity, and several pickings should be made ; the fruit should be removed when it has reached the required degree -of ripeness for the market it is intended to supply. The more distant the market the earlier the fruit should be gathered to ensure its arrival on the market in good marketable condition. In gathering fruit for export attention .should be directed to the degree of maturity rather than colour. . Much has been written about the necessity of picking to colour and colour standards, but this is apt to be misleading to the grower or picker, as, while the fruit remains on the tree to attain a high colour, it may become over-mature for •transport to the market. Select early picking is of great benefit, as the removal of the mature and larger fruit accelerates the “ sizing-up ” of those remaining, and also tends to improve the colour of such fruit. The fruit should be removed -carefully without damaging the fruit spurs or tearing out the stalks from the fruit. When picked the fruit should not be left standing in the sun, but removed as soon as possible to the packing-shed. A simple and reliable test for the maturity of apples is made by cutting an apple in half from cheek to cheek, and if the main vascular bundles are linked up the apple is not sufficiently forward to pick. Once the points .are unlinked, however, the apples are sufficiently mature for picking. Budding. When weather conditions are suitable and little difficulty is experienced in lifting the bark, budding may be proceeded with. When budding stonefruits it is advisable to make the horizontal cut at the bottom and the

vertical cut to go up instead of down (as in the usual practice of budding), as this lessens the gumming which so often occurs when budding stone-fruits. ' • Fireblight. , A sharp lookout for twig infection by fireblight should be kept where blossom infection was experienced. It is usually from the sappy growthsthat ooze develops, and their cutting-out and destruction helps materially towards preventing subsequent extension of the trouble. Care should be observed in keeping the pruning secateurs sterilized, and large cut surfaces should not be left unprotected. These should be covered with a bitumen emulsion or other suitable material. ■

—B. G. Goodwin, Orchard Instructor, Christchurch.

Citrus Notes.

Disease Control. Provided the weather has been hot and dry, citrus redscale, if present on the trees, will be hatching freely in most districts. An application of summer-oil 1-33 should be applied forthwith (see December Notes). Where infection is at all extensive, at least two applications should be made at an interval of about one month. Thorough spraying is essential,, and occasionally operators should examine a tree which they have just sprayed. If it has been done properly there should be no dry spots on any part of the trees, especially underneath and on top of the foliage, all branches, fruit, trunk, &c. Experienced growers who have taken the trouble to make' this examination have often been surprised to find that portions of treeswhich they, had thought to be well covered have received little or no spray. Now that the rush of spring work is over, a further examination of the treesshould be made for bark blotch and borer, and where these are detected appropriate action should be taken. Any old wounds which are showing signs of losing their protective covering should be " gone over ” again with bitumen emulsion or tar. If the latter is used, a mixture of coal-tar and Stockholm tar. in equal proportions is the best. Green Manuring.— lt is now time to give consideration to the important matter of green manuring. To obtain the greatest amount of growth from green crops for ploughing under in the spring, the seed should be sown early enough in the New Year to catch the first break in the dry weather and while the ground is likely to remain warm for a further two or three months. Generally, early February is a good month in which to sow lupins, either blue or white, field peas, tares, oats, or whatever is decided upon as being most suitable for the grower’s particular district. It appears to be agreed universally that one of the main requirements of citrus trees is organic matter or humus. In the older groves it is difficult to grow an adequate supply of green material between the rows owing to the spread of the trees and thecontinual tramping-down of the soil which takes place due to the fact that picking of lemons is carried on almost continuously. In those cases where the crops cannot be grown satisfactorily between the trees, it is necessary to consider growing them on adjacent ground and carting the material on to the orchard. Owing to this difficulty of growing green crops in a mature citrus grove (particularly in the case of lemons), the importance of the ploughing-in. of cover-crops in the first few years from planting, while the space is available, should not be lost sight of. The tendency to use the space between young trees for revenue-producing crops to the detriment of the supplying of humusshould be resisted. Where cowyard or sheep manure is available it should be used in large quantities. Young Trees. Young trees require attention during the hot dry weather. Light cultivation should be continued, and, if the rainfall is not sufficient, to keep the foliage from wilting, a good watering may be the means of assisting the trees to become well established. Watering, like most beneficial things,, can be harmful if it is overdone. Water lowers the temperature of the soil,.

and continual applications without sufficient ■ intervals for aeration and warming the ground cause a slowing-up of growth. If some of the trees are not doing as well as others, thought should be given to the cause of this condition, and, if possible, a suitable remedy applied. There may be weak spots in the shelter-belts, and where a number of young trees are exposed to strong winds it pays to shelter these individually by means of stakes and scrim. Some growers are under the impression that it is only the cold winds which cause damage, but this is not so, as hot winds or even temperate ones do just as much harm if the necessary force is behind them. The writer wishes to place special emphasis on this matter of sheltering young citrus trees, as several instances have come under his notice where blocks of the best trees procurable in the country have made no progress whatever during the past two years owing to their exposure to high winds. The aim of the grower is to get the trees into profitable production as early as possible. It is quite evident that a small expenditure for the purpose of supplying additional protection in the early stages of the orchard is repaid many times over by way of earlier and larger returns of fruit. The matter of fertilizing the young trees needs further consideration. Here again as with the water, care should be taken to see that this is not overdone. Dressings of artificial manure should be small and distributed over an ever-increasing area extending outwards from the tree-trunk. One application per year of superphosphate and potash should suffice. Nitrogen, in the form of sulphate of ammonia or nitrate of soda, may be applied with advantage twice a year, in September and again about January, using for trees in their first year slightly under half a pound well distributed at each application. Quickly acting nitrogen should not be applied late in the autumn, on the grounds that it may keep the young growth moving until the frosts arrive, with consequent damage to the tender shoots. For the first year the growth made by young orangetrees may be disappointing compared with that made by lemons under similar conditions ; but this is to be expected, as orange-trees often take about a year to become established. Pruning in most cases should be confined to the removal of growth which appears below the bud, and, in the case of shoots which are too rank, a light pinching-back may be practised ; but for the first year the trees should have almost a free hand to put oh growth which will help them to become firmly established. Even light laterals which are obviously too low down to be of use for the permanent limbs of the tree should be allowed to remain in the meantime, as they may afford useful shelter from the rays, of the sun during the hot weather. In cases where the shape of the tree is such that the trunks are exposed to the direct rays of the sun it is advisable to paint them with whitewash. This reflects much of the heat and keeps the limbs more nearly at air temperature. A good formula for whitewash is fresh rock lime, io lb. ; salt, i lb. ; flowers of sulphur, J lb. While the lime is slaking, add the salt and the sulphur, later thinning to the desired consistency. Grading and marketing Lemons. — Although most citrus-growers forward their fruit to a central packing organization which cures, grades, and markets it on their behalf, there are still a number of growers who are curing and packing their fruit themselves. A number of these do not appear to be conversant with the regulations relating to the sale for consumption within the Dominion of New-Zealand-grown fruit. A precis of the regulations may assist in clarifying the position for those not acquainted with their provisions. All lemons sold on the market must be contained in standard packages which shall be branded with the registered number of the owner of such fruit and marked with either the words “ cured ”, or “ not cured.” The words “ New-Zealand-grown Lemons ” must, also be branded on each case. If the word “ cured ”is used (and it is compulsory to use either “ cured ” or “ not cured ”), then the lemons must be graded into one of the five official grades for lemonsviz., Extra Fancy, Fancy, Good, Small Grade, or X Grade, and the grade mark, together with the count, branded

on one end of each case. Lemons for inclusion in any grade shall have a minimum juice content of not less than 25 per cent, by volume. For information as to the requirements of the various grades, the grower should apply to the Orchard Instructor for his district.

—A. R. Grainger, Orchard Instructor, Tauranga.