What are the key points of winter pruning techniques for apricot trees?
Brief introduction: Brown rot Brown rot is also known as fruit belly disease. In rainy years, if fruit-boring pests are severe, brown rot becomes epidemic year after year, causing a large amount of rotten fruit and fruit drop, resulting in great losses. 1. Symptoms It can infect flowers, leaves and fruit, with fruit suffering the most serious damage. (1) Floral organs: When flowers are affected, they turn brown and wilt, mostly...
I. Winter pruning of young trees and trees in the initial fruiting stage
Young apricot trees and those in the initial fruiting stage generally grow vigorously, with the canopy expanding rapidly, a large amount of new shoot growth, and frequent secondary and tertiary branching. Pruning at this stage should take into account both training and fruiting. The extension shoots of the main and lateral branches should be pruned lightly and left long, generally retaining 2/3 of the total branch length for heading back. Remove crowded branches, multi-forked branches, overlapping branches and vigorous branches that disrupt the tree form, and control the growth of competing branches and upright vigorous branches. For moderately growing, well-opened development shoots, leave them unpruned to promote the sprouting of medium and short shoots, increasing the number of fruiting branches; after flower formation or fruiting, cut them back promptly to train them into fruiting branch groups. Medium and short branches with wide angles form flowers easily and should be retained as much as possible to favor fruiting. For weaker-growing young trees, appropriate heading back is advisable; remove overly dense and thin weak branches, retain more healthy branches, and bend upright vigorous branches flat as auxiliary nurturing branches to promote the growth of thick, strong medium and short fruiting branches.
II. Winter pruning of apricot trees in the full fruiting stage
In the full fruiting stage, training is basically complete. As the tree ages, yield rises and gradually stabilizes, growth vigor weakens, and tree vigor gradually moderates. The main task during pruning is to adjust the relationship between growth and fruiting, maintain tree vigor, and extend the number of years of fruiting in the full fruiting stage. When pruning, according to branch vigor and the spatial conditions of each part of the canopy, thin out or head back appropriately to maintain a stable fruiting position and growth vigor. For extension branches at all levels, generally carry out moderate heading back so they continue to produce healthy new branches. For weakened main branches, lateral branches, perennial auxiliary nurturing branches, fruiting branch groups and drooping branches, cut back for renewal or raise the angle at positions with strong branches, so as to restore their growth vigor. For branches at the lower part of the canopy and in the inner canopy, pay attention to timely renewal and rejuvenation so they continuously produce new healthy fruiting branches. For overly dense and vigorous branches at the upper part and periphery of the canopy, cut back or thin out to improve light penetration into the inner canopy. Apricot trees have weak branching ability; for fruiting branch groups in all positions, long fruiting branches and moderately growing development shoots, as long as they are not overly dense, generally do not thin them out; heading back can be used to promote a small number of long branches, so that the middle and lower parts produce medium and short branches for alternating fruiting.
III. Winter pruning of apricot trees in the aging stage
In the aging stage, the extension branches of apricot trees grow weakly, new shoots are short, skeletal branches begin to droop, the interior of the canopy begins to become bare, fruiting occurs almost only on the canopy surface, and yield declines. The pruning task is to renew skeletal branches and branch groups, strengthen tree vigor, and extend the fruiting years. Use vigorous back branches with small angles in the middle and lower parts to replace the leader, and for properly positioned water sprouts, use and train them as skeletal branches and fruiting branch groups. For fruiting branch groups and fruiting branches, following the principle of "remove the weak and retain the strong," select and retain strong branches and strong buds for renewal pruning, to restore and maintain yield.