First, the basic pruning method: short cut, also known as short cut, refers to the pruning method of cutting off part of branches within one year, thus shortening their total length. Its main function is to stimulate the germination of lower lateral buds, promote the differentiation of new branches, increase the thickness of branch axis and change the extension direction of branches. Mostly used for the cultivation of backbone branches and large and medium-sized fruiting branches. Cutting young trees several times a year will weaken the growth of roots and branches and dwarf trees. Short pruning is often used in large and old fruit-bearing trees, which can renew and rejuvenate weak branches and enhance tree vigor, thus enhancing fruit-bearing ability, improving fruit quality and prolonging tree age.
1. technical requirements: the technical requirements of short-branch cutting include the selection and retention of cutting buds and the cutting method of cutting. Only when the operations in these two aspects are as correct and reasonable as possible can the direction and type of hair branches meet the intention of the trimmer, and the cut wound will heal as soon as possible, thus obtaining the best trimming effect. (1) Selection and retention of cut buds: cut buds refer to the buds closest to the cut position after the branches are cut short. When selecting and retaining the cut buds, the direction of the bud tip should be considered first, because the direction of the cut buds determines the development trend of the branches in the future. Generally speaking, the direction of cutting buds should mainly consider the original posture of branches and the posture to be adjusted in the future. If the original posture of the branch is too upright, in order to prevent the tree from growing and the light in the crown is insufficient, the outer bud should be selected as its cutting bud to make the new branch tend to open. If the posture of the original branches is too open, or even the branches tend to droop and weaken, then we should choose to cut the buds to keep the upper buds strong, so that the new branches tend to stand upright and restore their growth. If the branches meet and cross, the branches can be cut off with the left and right buds as the head, so that the newly issued branches develop to both sides respectively to avoid competing for space and blocking the wind and light.
Selection and retention of cutting buds
(2) Incision cutting mode: The incision cutting mode has a great relationship with the speed and effect of wound healing. The correct cutting method should be that the opposite side of the bud is cut down slightly on the inclined plane, with the same side of the bud high and the opposite side low, with the upper end of the inclined plane flush with the tip of the bud and the lower end flush with the base of the bud. In this way, the cut wound is smaller and easier to heal. After healing, the scars and branches from the cut buds are smoother, and the branches from the cut buds grow well. In order to consider the pruning efficiency, some people adopt the pruning method of flattening the top of the bud. In fact, there is no harm in using flat cutting for new buds with leaves during the growth period, but the speed of wound healing and the smoothness of new buds are not as good as the above-mentioned micro-oblique cutting method. Of course, if the slope is too big, the lower side can't cross the base of the bud, because the wound is too big, which will not only be difficult to heal, but also lose a lot of water and nutrients, which will affect the growth of new shoots of cut buds and cause the death of cut buds in cold and windy areas. Therefore, in general, the method of cutting branches with large slopes should not be used indiscriminately. Only when "pushing out the buds inside" needs to weaken the germination of the cut buds, the inclined plane of the wound is intentionally enlarged and used occasionally without cutting off the cut buds. The stake cutting on the bud, regardless of flat cutting, oblique cutting and wound size, will be difficult to heal because nutrients are not easy to flow in, forming a dry pile. Only in cold and windy areas in winter, in order to protect cutting buds from frostbite and trim vines before burying, short piles can be temporarily left for cutting. Leave the stump for cutting, and it needs to be trimmed again after germination in the next spring to remove the residual stump.
Shortcut cutting method
2. Technical method: The technical method of short cutting mainly classifies branches according to the severity of short cutting. Winter scissors include light scissors, medium scissors, heavy scissors, overweight scissors, hat scissors and broken table scissors. Summer pruning includes cutting tips and coring.
(1) Light cutting: It is also called light cutting, which means that only a short section at the top of the branch is cut off, so it is also called light cutting. If only the terminal bud is cut off, it is called decapitation or heading. If only a part of the terminal bud is cut off, it is called broken top or broken bud, and 1/3 ~ 1/2 is usually suitable for cutting off the bud. Because the lightly cut parts are mostly semi-full buds with small buds, the new branches formed are mostly medium and short branches, which is beneficial to slow down the growth and fruiting. This method is mostly used for varieties with high germination rate, and varieties with low germination rate are prone to "bare legs" without branches at the lower part after application. Light pruning is one of the main purposes of cultivating young branches and bearing branches.
Severity of shortcut and its reaction ①
(2) Mid-cutting: also called mid-cutting, it refers to the short cutting at the full bud in the middle of the branch. The medium and long branches germinate easily after cutting, which is beneficial to the growth of branches and the expansion of crown. Therefore, intermediate cutting can improve the branching ability of budding shoots and make their mother branches thicken rapidly. The method of middle pruning is usually used to cultivate the extension head of main branches and update the weak fruit branches
Severity of shortcut and its reaction ②
(3) Re-shearing: also known as shearing, refers to shearing at about 1/4 in the middle and lower part of the branch. Although this cutting method stimulates the branches greatly, because the buds in this part are mostly half full and small, the medium and short branches are still the main ones after cutting, and a small number of long branches can be made on the upper part. Therefore, heavy pruning is an important method to cultivate dense fruiting branches on young trees, which is generally used for varieties with low germination rate. In old trees, in order to control the flowering and fruiting of trees reasonably and promote the growth of branches and leaves, varieties with high germination rate can also be used.
Severity of shortcut and its reaction ③
(4) Overweight cutting: also known as overweight cutting and surface cutting, refers to cutting that leaves a small part of short branches at the base of branches. This cutting method generally has low branching ability, and only produces 2 ~ 3 medium and short branches, which is beneficial to weaken the branching potential, reduce the branching position and cultivate more compact small and medium-sized fruiting branches. It is often used to induce preparatory branches and transform strong branches. For some strong branch varieties, sometimes heavy cutting may make strong branches even deviate. In this way, when pruning next year, it is necessary to carry out "core digging" treatment, remove the straightness, remove the strength and leave the weakness. You can also use continuous overweight pruning in the growth period to cultivate more compact fruiting branches, which is called short branch pruning.
The seriousness of shortcut and its reaction
(5) Hat cutting: also known as hat cutting, refers to the cutting technology near the blind bud at the annual ring mark of a single branch or the annual ring mark at the junction of spring and autumn shoots. Hatching is a cutting method of medium and short branches, which is used to cultivate small fruit branches. According to the length of branches cut above wheel marks, hats can be divided into five types: dead hat, live hat, low hat, high hat and crooked hat. "Wearing a dead hat" refers to the method of cutting in the middle of the wheel mark in the middle of the branch, which is mostly used for a moderately weak single branch. The characteristic of its pruning reaction is that the new branches are easy to concentrate near the "hat" In order to promote more branches in the lower part, some fruit farmers also cut under the "hat" and cut off the residual piles after the branches are sent, which has a good effect. "Wearing a movable cap" refers to the method of leaving a few shriveled buds above the wheel marks for pruning, which is mostly used for a single branch that grows vigorously. It is characterized by adding more medium and short branches at the lower part and reducing long branches. "Wearing a small hat" refers to a method of cutting a living hat, leaving fewer shriveled buds above the wheel marks. "Wearing a high hat" refers to the method of cutting with a living hat, leaving more withered buds above the wheel marks. The higher the cap, the more beneficial it is to alleviate the branching trend and increase the number of short and medium branches, which is more suitable for cutting strong single branches with caps. "Wearing a crooked hat" is a method of overweight pruning at the base of the lateral braided branch after loosening the central branch.
Dressing reaction of wear cap and crushing platform
(6) Broken platform scissors: also known as broken platform scissors, it refers to cutting off the swollen tumor-like fruit platform on the fruiting branch. The general method of cutting the fruit table is to cut off 1/3 ~ 1/2 on the fruit table, so that the latent buds on the fruit table germinate and form new branches, which are called fruit table secondary branches or fruit table branches. The well-nourished auxiliary branches of fruit table can form flower buds in the same year and bear fruit in the next year. Table-breaking scissors are often used to reduce and update bare fruit tables with short fruit branches of apples and pears without secondary tips.
Dressing reaction of wear cap and crushing platform
(7) Softwood cutting and coring: The above five cutting methods are all from the perspective of winter cutting during dormancy. In the summer and autumn of the growing season, the new shoots with leaves are cut short, which is generally called twig cutting. If the pruning is very slight, just remove the tender growth point at the top of the new branch by hand, which is called coring in pruning. By changing the distribution and transportation direction of auxin and nutrients in new shoots, cutting and coring can weaken the apical advantage, control the vigorous growth of new shoots, increase the thickness of branches, improve the development quality of branches, promote the germination of new lateral buds in the same year, and form affiliated fruiting branches.
Pruning reaction of pruning and coring