First, weaken the top.

The top of the walnut tree has a strong advantage. When the upright branches and long-legged branches on the head grow vigorously, they can reach more than ten feet, which leads to the rapid growth of the crown vertically, and the middle and lower branches die year by year, which weakens the inhibition, but will promote the vigorous growth of the top and form a vicious circle. This is the main reason why the crown is high, big and empty.

Therefore, when pruning walnut trees in winter, controlling the strong head is the primary task. If it is too strong, thin the branches. It's too high. You must bow your head. The thinning of branches should start from the base of branches; When the head falls, the kerf must be braided, and the braiding should be 1/2 of the original mother branch.

Second, control the periphery.

With the growth of tree age, the outer branches of the crown will gradually elongate, the fruiting branches in the inner cavity will slowly die, the inner cavity will become empty, and the fruiting parts will move outward. This is the natural physiological law of plants, which will reduce the yield and quality. To change this natural phenomenon, the peripheral branches must be controlled reasonably, and the long backbone branches must be retracted in time.

The specific operation is not as simple as shrinking the long branches into short branches, but depends on the containment ability and baldness of the branches. If there are branches behind, the binding force is balanced, and there can be fewer branches or no branches from the periphery; If the posterior baldness is serious, it can be retracted properly or more branches can be thinned from the periphery.

Third, balance the tree potential.

In winter, pruning is the most important to balance the tree. A pruning expert with many years of practical experience, the trees pruned in winter have many short branches, few long branches, many thick branches, few fine branches, many inner branches and few outer branches, and the fruit on the tree is the same size as the whole tree, which is related to the tree potential balance during pruning in winter.

In the process of field work, after controlling the strong head and retracting the periphery, it is necessary to comprehensively consider the full crown, support the weak part and weaken the strong part, and if necessary, artificial injury can be used.

Fourth, make up for the space.

This is an important link for high and stable yield. Only in this way can the crown be full, the chamber not empty, the effective volume be fully utilized, and the plant can reach the highest yield every year. Measures should be taken to make up for the space when logging in winter.

When the tree is in full fruit stage, the volume of 1 m3 in the crown cavity can normally carry 5 kilograms of dried fruit, so the effective volume cannot be wasted. If you encounter a space of more than 30 cm in winter pruning, you can select the surrounding branches in winter pruning, and then extend the sprouted new branches to fill the space in the second year.

Fifth, repair the branch group.

Results The number of medium and short branches on the big tree should account for more than 85% of the total branches of the whole tree. How to cultivate fruiting branches and how to deal with the use of medium and short branches is the most work of plastic pruning in winter.

When the walnut tree bears fruit:

Walnut trees generally bear fruit in 1- 10. Different varieties have different fruiting time. Grafting propagation of early-bearing walnut varieties usually takes one to three years to bear fruit. The different fruiting time of walnut trees will also be affected by the climate and management methods of the year. In order to promote the fruiting of walnut trees, it is necessary to ensure strong seedlings and reasonable cultivation management of walnut trees.