Prune (1) dense trees with tree rootstocks.
(1) Accelerate the growth and increase the amount of branches and leaves. For the new shoots of that year, when they grow to about 30 cm, we should remove the heart, promote secondary branching and increase the amount of branches and leaves. For trees with weak growth, cut short branches in winter. Generally, the growth branches extracted in the first few years of planting are kept. For strong trees and strong branches, pruning is adopted after spring germination, that is, late pruning, so that the growth potential difference between the cut buds and the lower axillary buds is reduced and the branches are increased. (2) Maintain the tree potential and relieve the branch potential. After several years of planting, the trunk branches of densely planted trees should continue to be properly pruned to maintain a certain growth potential to maintain the tree potential. Generally, the growing branches are lightly cut and slowly released, and appropriate treatment is carried out in the growing season, such as taking branches, picking cores and pulling branches. For some leafy trees and leafy branches, pruning methods such as girdling and inverted peeling can be used to control the situation and promote flowering. At the initial stage of fruiting, keep more fruits, press branches with fruits, promote branches to become flowers, reduce large branches and cultivate more branches. (3) Control the crown and keep the fruit yield. When the plants are close to each other, the length of the main branches should be controlled, so that the main branches can grow moderately, the upper part is sparse and the lower part is dense, and the inside and outside are transparent. After fruiting, control the fruiting branches to be close to the main branches to avoid the outward migration of fruiting parts. There are many lower branches in densely planted pear trees, and the super-high crown is easy to affect the growth and development of the lower branches, so it can be left in the upper part and outside to improve the light. The height of the tree can be controlled by changing the head and shrinking the weak branches.
(2) Dwarfing, close planting and pruning
Hedge cultivation mode is generally adopted, with and without supports. The task of pruning is to solve the problem of ventilation and light transmission. (1) control the height of the tree, the crown height is generally 2 ~ 3.5m, the hedge width should not only be bald inside, but also the hedge row spacing should be controlled to make the lower part of the crown grow normally. Reduce the level and number of backbone branches and focus on cultivating fruiting branches. (2) Control the crown width. The densely planted single pear tree occupies a small area, so the growth of crown branches should be controlled, and the big branches should be retracted or thinned in time. First, young trees are pruned again 1 ~ 2 years to promote their vigorous growth, and then released slowly in the next few years, and then retracted after bearing fruit to control the branches and crowns with fruit. Second, in the growing season of adult trees, bud and shoot should be wiped in time to make the crown dense. Root pruning is also an aspect of crown control. For wangshu, root pruning is carried out to promote the growth of lateral roots.