PRUNING AND PESTS.

Northern Advocate, 1 August 1924, Page 2

PRUNING AND PESTS.

LOCAL DEMONSTRATION. BY MR. P. EVERETT. At the orchard of Mr T. H. Steadman, Mill Road, yesterday afternoon Mr P. Everett, Orchard Instructor attached to the Department of Agriculture, gave a pruning demonstration and also had a few words to say re garding pests and diseases in the orchard. There was an attendance of about 40 ladies and gentlemen. Before going on with the demonstration Mr Everett stated that he -was very anxious to meet the local fruitgrowers and also those interested in fruit cultivation. He had been growing fruit for the best part of his life and was connected with the industry commercially, as he owned a large orchard in Nelson. In the course of his demonstration, he might be wrong about some things, as work in an orchard varied according to climate and he had not been in the North very long. Most principles applied to pruning right throughout New Zealand, but some Systems adopted in the North miglit be a little different from those adopted in other parts. It had been said that the two worst pests in connection with fruit growing "were the eodlin motli i and the orchard instructors," (laugh- ; ter), but he did not think that the latter deserved that. He might be able to be of some assistance to his bearers and hoped that they would- not ' look upon the orchard instructors as J nuisances. YOUNG TREES. There were three principles laid down in pruning young trees: — 1. For uniformity size and shape of: fruit. 2. Good quality and colour. 3. Heavy crops over a long period with the least possible cost. To obtain these principles nature helped very largely in the pruning of trees, but could not be entirely depended upon. For instance, root pruning was against nature. . When planting young trees in a locality subject to high, and strong winds it was advisable to head them well back to, say, about six inches from the ground. In localities not subject to boisterous winds they should be headed from a foot to IS inches from the ground. If the roots had been cut the top must ! be cut correspondingly in order that i the tress may come away quickly. It jwas advisable to prune fairly severely in the first two years as it made for j better growth in the succeeding years, i If this rule were adopted with young trees they would give an abundance of fruit in years to come. The formation of the tree at the start should be ! composed of about three or four '' branches. The next year there shouM be six or eight brandies or leaders, and the third year 12 or 16 leaders. A tree should be cup-shape in order to allow of the sun getting to the middle of the tree, thus ensuring good fruit. Two- circles of leaders was the best for the first three years, after which it was advisable to let other branches pome out. These should be trained between the then existing leaders. "With two circles of leaders the outside would usually crop the heaviest and as the fruit grew the weight would weigh the branches down and allow the sun to penetrate the centre. The outside leaders should not be allowed to bear too much fruit, as the branches having been weighed down excessively would not, after the fruit had been removed, go back in their places. Trees that ! had a tendency to grow straight could be made, to spread by pruning. This I was effected simply by leaving a. stump | above the bud, which made the bud 1 grow out at a wider angle. Another method was to cut just above the bud which was growing inw T ards or the bud above the one required for fhe leader. The top one grew into the centre and the lower one out at a greater angle. ' Next year t-iey must cut off the ingrowing 1 lid. When a stump wis left ;ib:;ve the bud it must be cut off at the next year's pruning, as although it was dead it had a weakening ef'iV't on the branch. ,Thc methods given would also apply very >\lrgely in cutting back an old tree. Old trees should not be allowed to become ovcrshaded; the sun must have access if I good sound fruit were required. By cutting out a lot of branches from an old tree they would get a lot of fruit —not decrease the crop, but in most cases increase it. Trees that were shaded were simply a breeding ground for woolly aphis and all other orchard pests. By proper attention to pruning every tree should have fruit spurs along the leaders. With some trees, of course, it was difficult to attain lhis, but in the majority it was easy. Summer pruning, too, helped the formation of fruit buds. Keeping the laterals short was the main principle of ing old trees. It was much hotter t) have fruit on the lower branches of a tree as against the top branches. A vigorous tree with a good rcot growth did not require hard cutting back. In light volcanic soils, such as obtained in the North, there was very little need for root pruning; in fact, it was only needed in extreme cases of vigorous growing trees which would not crop.

STONE FRUITS. Peaches and Nectarines should be hard pruned at the top and kept well back. If allowed to grow too tall the quantity of fruit got less and was smaller in size. By stopping top growth the fruit spurs were sent out on the lower main branches, but care should be taken to see that there was plenty of ventilation. Silver blight was very common in these trees and for which there was no known remedy. It usually made its appearance in old trees that had been allowed to grow wild and then cut back. By careful attention to pruning each year silver blight would be avoided. All dead twigs must be removed from these trees and prunings especially should he burnt. It was all right to bury the leaves and mummies, but they must be buried in a place where there was no chance of them being brought to the surface in the following spring. The only way to get a good shape in a pear tree of the keeping variety was to leave a fair length of growth after shaping and then head back a year later, not too hard, so as to give the fruit a chance to pull the branches out. It was a matter of careful judgment, as if the wood were left too long there was a chance of the limbs breaking with the weight of the fruit. LEMONS AND ORANGES. In most cases, after the first shaping, these trees did not require much pruning. All cross branches, however, should be cut out and the trees should not bo allowed to become too thick in the centre, particularly in the case of oranges. In planting out they should be cut back the first year, the same as the pip fruits. Brown rot in lemons germinated in the soil owing to an excess of water. The best thing to do was to keep the branches .12 to 18 inches off the ground so that water could not splash up on to them. In the ease of borer in lemons it was advisable to cut the branches off. A good remedy was to stick a hat pin down the hole and so %kill the grub, or to pour in benzine in the hole and plug it up with soap. The fumes from the benzine would kill the borer and save the tree.

j Foot rot in lemons must be caught t oarly if the tree were to be saved. The i first indication of foot rot was that the leaves appeared sickly and yellow. I Everv particle of the dead bark should i be cut away with a sharp knife and the affected part given a coat of Stock- > holm tar. This was the only way to stop it. The steel blue ladybird, specimens of which were shown by the lecturer, was the deadly enemy of scale on citrus fruits and the action of these insects had dispensed with the necessity of spraying. QUESTIONS. In answer to questions the speaker stated that Alphelinus Mali (a small .fly about half the size of a sand fly) had been proved to entirely eliminate woolly aphis. Supplies could be obtained from the Cawthron Institute, Nelson. . Brown rot was a fungus disease which fed on dead leaves in the winter, .then on the young leaves and later on the fruit. He had no confidence in .injecting fluids into the tree. The -best method of checking the disease | was spraying with a strong winter mixture, say 8 —6—40 Bordeaux, to be followed a little later with a 3—4—50 Bordeaux. When the fruit was halfgrown, a spray of 1—2 —25—30 lime and sulphur spray and again a few days before the fruit was picked. Mr Steadman said that he had found spraying with lime-sulphur just before rain had been very effective, and , Mr Everett agreed that the warm rains of the North were very conductive to the spread of brown rot. .'Red oil was not a complete cure for woolly aphis. It would keep the disease down, but would not eradicate it. Alphelinus Mali was the cure. The Mussel scale was very prevalent and had to be kept down according to the Act. The best means of control was red oil spray just before the buds ■burst, and if very bad two summer sprays of lime and sulphur with Blade : Leaf 40 when the scales were hatching, | Avhich in this district would be about 1 the end of October or beginning ot v\ T ovomber. This would act as a biV ■■ check. It would not kill the old scale, but it would stop it from breeding.