The structural characteristics of (1) sparse-layer trunk tree: it has a central trunk about 50 cm high, and * * * has 6-8 main branches with 3-4 layers. The first layer has three main branches, the opening angle of which is about 60 ~ 70, and each main branch has 4 ~ 6 side branches; The second layer has two main branches with an opening angle of 45 ~ 50; There are 1 main branches on the third and fourth floors, and the opening angle is less than 45. There are 1 ~ 3 side branches on the main branches of the second, third and fourth floors. The spacing between the first and second layers is about 80 cm, and the spacing between the second, third, third and fourth layers is 50 ~ 70 cm. Backbone branches at all levels should be equipped with various types of fruiting branches.
The advantages of this tree shape are moderate potential, stable fruiting position, high and stable yield and long fruiting period. The disadvantage is that the technical requirements are high, the pruning amount is large, the generated parts are easy to move out, or a tree with strong upper part and weak lower part is formed, and the early yield is low.
This tree is suitable for hilly areas with poor conditions and places with poor soil.
Characteristics of plastic pruning: after planting seedlings, leave 60 ~ 70 cm to fix the stems. In that year, there were 3 ~ 5 new branches growing vigorously, among which the tall branches grew vertically as the center, and the other branches extended around as the main branches, with an opening angle of 60 ~ 70 in autumn. When pruning in winter, leave 50 ~ 60 cm of central branch for cutting, and cut the rest branches lightly and slowly. In the summer of the following year, the extension heads of the main branches with strong growth potential were cored to increase the branches. When pruning in winter, the treatment method is the same as that in the first year. In the summer of the third year, measures such as removing the core and twisting the tip were taken to increase the number of branches. Make the crown of the tree expand year by year. During four to five years, the main branch is not cut off by the strong, so that its terminal bud can be extended and become an extended branch; There are often 1 ~ 2 growth branches from the terminal bud down to the vicinity. If the position of these long branches is suitable, they can be reserved for lateral branch culture, and the useless ones can be thinned out. If the trees entering the initial fruit-bearing stage bear too many fruits and the tree vigor is weak, the fruit can be thinned and the fruiting branches can be adjusted appropriately. If there are too many branches and the main branches are dense, some main branches can be thinned out. Every year, the trunk of the central leadership will be cut short, and when the crown reaches the ideal height, it will be happy. (2) The morphological characteristics of clump trees are similar to those of natural happiness trees, but there is no trunk. The trunk directly produces 4 ~ 5 main branches that grow evenly near the ground, and there are lateral branches and fruiting branches on the main branches.
The tree has the advantages of easy shaping, light pruning, wide crown, early fruiting and simple management. The disadvantage is short life.
Characteristics of plastic pruning: leave 20 cm stem after planting, and 3 ~ 5 branches will occur in that year; From June to July, 30 ~ 40 cm should be reserved for the more vigorous branches to collect cores, so as to promote the secondary branches, balance the growth potential of branches, increase the branch order and bear fruit early. In the spring of the following year, according to the growth potential, the branches less than 70 cm in length are slowly cut off and allowed to grow; Branches over 70 cm should be shortened by 20 ~ 30 cm. When the number of branches is insufficient, leave 20 ~ 30 cm strong branches for pruning, and leave all the cut buds outside. In the spring of the third year, only a few vigorous branches were cut off and adjusted, and the rest were slowly released. After three years of adjustment, the tree is basically completed. (3) The natural happiness tree is characterized by no central trunk, the trunk is 20-40 cm high, and 3-4 main branches are distributed around to form a crown, and the opening angle of the main branches is about 40. There are 4 ~ 5 lateral branches on each main branch, which are arranged in the air, with an opening angle of 60 ~ 70, and many branches extend uniaxially, bearing various bearing branches on them. The crown is about 3 meters high and round.
The tree has the advantages of less pruning, easy molding, early fruiting, open crown, ventilation and light transmission, and good fruit quality. This kind of tree is short, easy to manage and suitable for cultivation on hillside. The disadvantage is that the crown is easy to close, the crown is easy to shift and the fruiting life is short.
Characteristics of shaping and pruning: after the stem is fixed, if the cutting branches grow upright and vigorously, leave 15 ~ 20 cm for coring control; When the growth of cutting branches is not prosperous, you can choose to leave the main branch and pinch it with the branches below the main branch for 30 ~ 40 cm to promote the growth of branches and cultivate the extension branches and side branches of the main branch; If the growth is still vigorous, in early July, the extension branch of the main branch is reserved for 30 cm for the second coring, and the other visual branches are re-cored 1 ~ 2 times to control the growth. In the following spring, the main branch is 40 ~ 50 cm long, and the rest branches are slowly put or lightly tied. If the extended branches are still growing vigorously, continue pinching in the growing season, speed up the cultivation of lateral branches, control the pinching and kinking of competitive branches and flourishing branches on the back, and cultivate fruiting branches. Continue to adjust the angle of the main branch in autumn and choose to keep the side branch. Spring and summer pruning in the third year is the same as that in the second year. After three years of promoting branches and expanding crowns, the tree shape was basically completed and entered the fruiting period. The whole tree is basically not cut, only individual branches are adjusted, branches are thinned or thinned, and branch density is adjusted. (4) The improved trunk structure features are similar to the free spindle shape of apple trees, and the trunk height is more than 50 cm. The trunk is equipped with an angle of 8 ~ 10, which can be divided into 2 ~ 3 layers. The main branch spacing of each layer is 15 ~ 20 cm, and the interlayer spacing is 30 ~ 60 cm. The main branches can also rotate on the central trunk without layering. Generally, there are no side branches on the main branch.
The tree has simple structure, few main steps, easy shaping, good ventilation and light transmission, easy flowering, early fruiting, high yield and excellent quality. Used for dry varieties and rootstocks with strong soil fixation. Suitable for close planting and mechanized pruning, it is a widely used tree species in the United States and other countries.
Characteristics of plastic trimming: the plastic trimming in the nursery can be set higher, and generally about 65 cm is reserved for coring; Leave 70 cm in the nursery to finalize the design. Pruning in summer of that year was mainly based on the opening angle of main branches (70 ~ 80). The middle trunk and extension branches can be picked when they are flourishing, but not when they are flourishing, and the competitive branches can be controlled again. When pruning in the spring of the following year, the extension branch of the central main branch is generally cut off by 40 ~ 50 cm, and the cutting length depends on the number of main branches selected at the lower part. When the number of lower main branches is large (3 ~ 4), the cuttings can be longer. Slow down or lightly start the selected main branch and carve buds on it to promote branching. Pruning in the growing season, the treatment of extended branches and competitive branches in the middle trunk is the same as that in the first year; The opening angle of the main branch selected in that year should be controlled by re-coring the main branch selected in the first year and the top of the back; Other branches can also be controlled by coring to prevent multi-head elongation, promote the germination of medium and short branches in the middle and rear parts, and increase the number of bearing branches. The spring pruning and growing season pruning in the third year are the same as those in the second year. After three years of shaping and pruning, the tree shape is basically completed. In addition, happiness depends on the height of the tree and the growth of its main branches. If the main branch is strong, you can be happy in the future; Weak main branches can lead to early happiness.
In the process of tree shaping, we should pay attention to opening the angle of main branches in time to make each main branch grow nearly horizontally. (5) The structural feature of the slender spindle-shaped tree is that the stem is about 60 cm high, and the main branches of 10 ~ 15 are cultivated on the central trunk, and the opening angle of the main branches is 80 ~ 90. Culture fruiting branches on the main branches. The lower main branch is slightly longer, and the upper main branch gradually becomes shorter, showing a slender spindle shape. The trees are slender, suitable for short and dense planting, and are mostly used for semi-short rootstocks or short rootstocks, and the plant spacing is 1.5 ~ 2.5m× 4m.
In plastic surgery, the central leadership trunk is generally not short, and most of them use the golden mean competitive branches to change their heads, so that the central trunk bends and extends, and the tree height is kept at about 2.5 meters.