(1) dormant pruning
Pruning in dormant period is the basis of pruning of big cherry all year round, in order to solve the contradiction between growth and fruiting and improve the scenic conditions in the tree as a whole. Pruning before germination is also suitable for dormancy pruning. Commonly used techniques include cutting short, spin drying, shrinkage drying, dewatering and so on.
1 shortcut. Short cutting is a common method for pruning big cherries. According to the degree of pruning, it can be divided into light pruning (pruning to length 1/3), medium pruning (pruning to branches of 1/2), heavy pruning (pruning to branches above 1/2) and extremely heavy pruning (pruning to hidden buds at the base). The main function of short cutting is to increase the density of branches, promote vegetative growth and rejuvenate branches. Moderately cutting off the extended branches of the main branches is conducive to increasing the number of branches, expanding the crown and promoting early formation and early fruiting.
2 throw. That is, annual branches are not cut, which is the most commonly used method to prune big cherries. Its function is completely opposite to that of the nipple. It is mainly to relieve tree vigor, adjust the number of branches, increase the number of fruiting parts and flower buds, and improve the fruit setting rate. Therefore, in order to bear fruit and yield early, in the plastic pruning, except the extension branches of the central trunk, all other branches should be cut short, and the degree and time should be mastered, so that the branches can be shrunk and rejuvenated in time after the fruit becomes weak.
③ thinning branches. Thinning branches can improve the landscape conditions in the crown and improve the fruit yield and quality. For big cherry, except for diseased branches, broken branches and dead branches, other branches should be treated as little as possible or not. This is because there are few branches in the early stage of big cherry trees, and thinning branches will inevitably cause wounds. Compared with other tree species, the wound healing of big cherry is slow, and the gum is easy to flow, which seriously weakens the tree. In particular, thinning the big branches will make the trees weaker. So try to be less sparse or not sparse. Even if it is passed, it should be carried out as soon as possible.
④ Retraction. That is, the short section of perennial branches. Shrinking and pruning the fruiting branches can make the remaining branches and buds get more nutrients and water, which is beneficial to growth and flowering. Proper shrinkage and pruning, moderate results, can keep the tree moderate and strong. Therefore, it is necessary to master the degree and time of shrinkage so that it will not grow too strong or too weak because of shrinkage.
(2) Pruning in growth period
Pruning in growing season refers to pruning from germination to defoliation, especially in summer. Pruning in growth period is based on pruning in dormancy period, which further improves the scenery conditions in the crown and promotes the rational distribution of nutrients, thus saving nutrients and promoting flowering and fruiting. Pruning in growth period usually adopts methods such as pulling branches, removing cores, cutting tips, removing sprouting, thinning branches, girdling, and carving buds.
(1) Pull the branches. Pruning during dormancy cannot solve the problems of ventilation, light transmission and polarity of trees at one time. If some big branches are cut too much in winter, they need to shrink again, causing unnecessary losses to the trees. In the growing season, by pulling branches, the growth potential of the branches can be alleviated, the single bud branches in the middle and lower parts of the branches can be promoted to be transformed into bouquets or short fruit branches, the growth speed of the branches can be controlled, and the trees can be compact. The time to pull branches can be spring, summer, autumn and winter, and summer and autumn are the best. Because the tree has been basically shaped at this time, the density of branches, the thickness of leaf curtains and the advantages and disadvantages of indoor scenery conditions are obvious. On the other hand, at this time, when pulling branches, the tree body is relatively flat and the back is not easy to fall. The branch pulling angle of each group is kept at 80 ~ 90 degrees.
2 pick the core and cut the tip. Picking refers to removing the tender part of the new tip before the new tip becomes hard, which is the most widely used method in summer pruning of big cherry. Core-picking of young cherry trees has the functions of controlling vigorous growth of branches, promoting tree density, increasing the number of branches, promoting branch transformation and accelerating crown expansion. According to the experiment of cherry young trees with coring in summer in Lin Dongmao experimental station, the average branch length can be shortened obviously and the number of buds of annual branches can be doubled.
Cutting off shoots refers to cutting off a part of new shoots, which is often carried out when the work is not timely and it is not convenient for new shoots to pick cores or expand crowns. Because the pruning degree of pruning is greater than that of core removal, the effect of pruning is also stronger than that of core removal.
Except MengMeng. It refers to removing useless or harmful buds from spring to early summer. The purpose of germination is to preserve nutrients and prevent dense branches from closing and affecting lighting and ventilation conditions. Therefore, the hidden bud branches, long branches and over-dense sprouting branches that hinder the growth of backbone branches at all levels should be removed in time.
4 Sparse branches. The effect of thinning branches in summer is often better than that in winter. Summer pruning is generally carried out after fruit picking. Its purpose is to remove the perennial branches that are too dense, too thick and seriously affect the light, so as to improve the scenery conditions in the crown and balance the tree potential. After fruit picking, the pruning wound is easy to heal, and the tree vigor is weakened slightly.
⑤ girdling. Girdling of big cherry can promote flower bud formation, improve fruit setting rate and fruit quality, especially pulp hardness and sugar content. However, the wound heals slowly after the big cherry is tied, and it is easy to have gum flow. So use it with caution.
6. Carve flower buds. It means that before or at the initial stage of big cherry germination, the next crescent-shaped tissue is cut off at the position 0.5 cm above the axillary bud of annual branch or the single bud branch of perennial branch, and the tissue thickness is about 65438 0 mm; You can also use a small saw blade to pull horizontally above the bud to the depth of the xylem. Because the epithelial layer and a small amount of xylem tissue of the bud are cut off due to the carving of the bud, nutrients can be prevented from being transported upward and concentrated on the bud or single bud branch, which stimulates the germination and branching of the bud. Bud carving can significantly improve the branch forming ability and flower forming rate of big cherry, which is the key technical measure for early high yield of big cherry.