(1) The common methods of winter pruning are as follows:
(1) Short cutting This method is the same as pruning other fruit trees, that is, cutting off part of the annual branches of 1. The degree of short cutting should be determined according to the thickness, length, variety, tree potential, short cutting purpose and other factors. The function of young tree short cutting is to stimulate the bud germination under the section and produce 2 ~ 3 long branches, thus rapidly expanding the crown, increasing the total branches and leaves of the whole tree and increasing the fruiting parts; On the left, middle and lower branches, promote a certain number of short fruit branches to bear fruit in the second year; Short cutting at full fruit stage can keep the tree vigorous, the fruit-bearing part stable, delay the outward migration of the fruit-bearing part and keep the yield stable; Short cut trees in old age can promote regeneration and rejuvenation.
② Retraction is also called contraction shearing. That is, cut the perennial branches to the base of 1 perennial branches or branches of perennial branches. Shrinking and shearing can weaken and control the growth of mother branches in inappropriate parts, promote the growth of late branches or stimulate the germination of latent buds, and change the elongation direction and angle of various elongation branches.
③ Thinning is to cut off branches from the base. The main objectives of thinning are: competing branches on the back; Overdense branches, cross branches, whorled branches and adjacent branches near the cutting mouth in the middle and upper part of the crown; At the same time, it can inhibit the former from promoting the latter and improve the light transmission conditions of the phoenix in the crown.
(4) Slow release is the same as other fruit tree pruning, except that it is not cut. Slow-release methods are mostly used for young trees and flourishing branches, aiming at slowing down the vegetative growth potential of these branches, forming more short fruit branches in the middle and upper parts of the branches, increasing the fruiting parts and increasing the yield.
(2) Summer pruning and growing season pruning are collectively referred to as summer pruning or growing season pruning. The purpose of summer pruning is to increase the number of branches, increase the total number of branches and leaves of the whole tree, rapidly expand the crown and promote the formation of flower buds, so as to achieve early fruit and high yield.
Main methods of summer pruning:
(1) De-sprouting, that is, after sprouting in spring, timely wipe off the inappropriate and excessive dense buds or shoots to reduce nutrient consumption and make the remaining branches get sufficient nutrition and light. This method is mostly used for young trees. It is best to smear the bud as soon as possible, and the length of the tender tip should not exceed 3 ~ 5 cm. At this time, the branches are not lignified, so they can be erased by hand, and the wounds caused by them are easy to heal; When old trees are regenerated, many useless branchlets are easy to sprout near the sawing mouth and should be erased as soon as possible.
(2) Some varieties of young trees are easy to attract some vigorous upright branches, resulting in the crown not opening. For this kind of branch, it can be pulled into a certain angle with a rope after the sap flows out and before germination, so as to slow down the growth, promote the growth of fruit branches and bear fruit early. The angle of branch pulling should not be too large, and 45 ~ 50 degrees is appropriate. If the angle is too large or flat, the upright branches will flourish on the back and still flourish, affecting flowering and fruiting.
For this kind of upright flourishing branch, if it is not cut or slowly pulled, some fruit branches can also be formed in the front (upper) part, but the lower part is easy to be bald after fruiting, which reduces the fruiting position and affects the yield and quality.
(3) Core picking is the tender part of the new tip. For long branches, regenerated branches, elongated branches and upright intermediate branches growing on the back, they germinate at suitable positions in the crown, and the light conditions are good. When the new shoots are about 40 cm long, the time for coring is better. However, the extended branches of the main and lateral branches at all levels and the branches replacing the extended branches can be coring-free, such as increasing the angle and increasing the order of the branches, but the number of coring can not be too many, so as not to enrich the branches.
About 10 days after the new shoot is cored, the lower part can be branched and lignified. However, if the core is removed more than three times, it may cause freezing damage when the branches are not fully grown, or it may weaken the tree because of too many branches.