(1) plastic surgery
The suitable tree shape of persimmon mainly includes sparse trunk shape, natural open trunk shape and changing trunk shape, and the tree shape should be selected according to the comprehensive factors such as variety characteristics, planting density and topography.
1. Sparse layer shape of trunk
The stem height is about 1m, and the persimmon-grain intercropping can be increased to1~1.5m. The main branches are distributed in layers on the central stem. 3 on the first floor, 2 on the second floor and 1 on the third floor. The upper and lower layers of main branches are staggered, with an inner distance of 30-40 cm, an interlayer spacing of 60-70 cm and a base angle of 50-70. There are 2~3 lateral branches on each main branch, the distance between the two lateral branches is about 60cm, and both the main branch and the lateral branch are fruiting branches.
2. Natural happy shapes
The trunk is 40~60cm high and has three main branches with an included angle of 120. The main branch spacing is 20~30cm, the bottom angle of the main branch is above 50, and the lower main branch angle is larger. Two or three lateral branches are planted on each main branch, the first lateral branch is more than 50cm away from the base, and the second lateral branch is more than 30cm away from the first lateral branch. There are fruiting branches on the main branches and side branches.
3. Change to trunk shape
The stem height is 50~ 100cm, and 4~6 main branches are scattered on the central stem. The distance between every two adjacent main branches is 30~50cm, the lower part is larger than the upper part, and the bottom angle of the main branches is 50 ~ 70. Leave two side branches on each main branch, with a distance of about 50cm, and the top 1 main branch 1 side branch. After selecting and leaving the main branch, saw off the central trunk above the uppermost main branch to complete the modeling.
(2) Pruning
1. Winter pruning
(1) young tree pruning
Young trees grow vigorously, with strong apical dominance, small branching angle and long branching. The main task of pruning is to cultivate the skeleton, open the angle, adjust the tree shape, properly prune and adjust the tree nutrition, so as to lay a good foundation for early fruiting and high yield.
When pruning, according to the requirements of plastic surgery, select branches with appropriate positions as main branches and side branches. Cut the extended branches of the backbone branches at all levels at appropriate positions to enlarge the crown, increase branches and cultivate a stable crown skeleton. The branches developed in the crown are less sparse and more cut, and the cultivated branches enrich the inner cavity to prepare for early high yield.
(2) Pruning fruit trees
At the initial stage of fruiting, persimmon trees are vigorous, the crown is expanding and the yield is increasing. After entering the full fruit stage, the tree body is relaxed, the tree posture is open and the crown is stable. Later, with the growth of tree age, due to shading, the inner cavity branches gradually weakened or even died, and the generated parts moved outward. The principle of pruning in this period is to stabilize the tree body, ventilate and transmit light, cultivate fruiting branches in the inner chamber, prevent the fruiting parts from moving out and prolong the full fruit period.
When pruning, the extension branches of the backbone branches at all levels should keep the angle and maintain the growth potential. Results The planned yield should be determined according to the variety, tree age, tree potential and cultivation management, and the number of reserved mother branches should be calculated and evenly distributed in the crown. The well-developed annual branches of persimmon trees are good fruiting mother branches in the following year, and the top 1~3 buds are mostly mixed buds, which can produce fruiting branches and cannot be easily cut short. When the bearing branches are dense or excessive, the weak branches should be removed, the strong branches should be kept, and some of them should be thinned or cut short as spare branches. There are more mixed lateral buds in the overdeveloped fruiting mother branches, which can be shortened appropriately to reduce the fruiting position. The fruiting branches of persimmon trees generally grow weakly after fruiting, and it is difficult to become fruiting mother branches for many years. Therefore, the fruiting branches should be shortened as reserve branches. However, varieties with strong continuous fruiting ability such as small calyx and small batter can still form flower buds after strong fruiting branches and become fruiting mother branches, so attention should be paid to their utilization.
Persimmon shoots have a short life span, which leads to weakness or death after 2-5 years. However, the cryptobud has long life and strong germination ability, and it is easy to form regenerated branches. When pruning, the branches that are too high and too long in the crown retract, which promotes the regeneration of the branches behind and controls the outward movement of the resulting parts. Sparse dense branches, cross branches, overlapping branches, diseased branches and dead branches in the crown to facilitate ventilation and light transmission. Short and rejuvenated slender perennial weak branches. When you have time, grow long branches and short bamboo shoots and cultivate fruiting branches. If there is no time, they become thinner from the bottom.
(3) Pruning of aged trees
Old persimmon trees grow weakly and have no obvious extended branches. The crown of the tree began to wither, droop and shrink. Branchlets and branches in the crown are constantly dying, and the bald part is increasing day by day. The branches behind the main branches grow in vain and naturally renew. In this period, the pruning amount should be large and the retraction should be heavy, so as to promote the regeneration of branch crown and prolong the bearing life.
When pruning, it is shrunk according to the aging of the big branches and the baldness behind them. Generally, it is carried out on 5-7-year-old or even older branches. Where there are new branches or long branches, they shrink back and let the new branches grow forward instead of the original branches. The retraction of big branches should be mastered flexibly, one branch is aging and the other is retracting, and the whole tree is aging and the whole tree is retracting. Persimmon has a long life, and its main branches can be updated several times in a lifetime. Only timely renewal can restore the vitality of the tree.
summer pruning
(1) bud wiping
After sprouting and before lignification. The young tree erased all the buds under the plastic belt. A large number of new buds will sprout at the intersection of the main branches, near the incision or at the arched part of the big branches. From April to June, the upward or downward new shoots will be erased, leaving 1~2 new shoots at the lower side to cultivate the mother branches.
(2) Choose the heart
During the shaping period of young trees, lightly cutting the elongated branches of 40~50cm can promote the growth of secondary branches and speed up the shaping. Leave 20 ~ 30 cm for coring branches with vigorous development, which is beneficial to culture fruiting mother branches. Leave the valuable tendrils on the tree for 30 ~ 40 cm for coring, and cultivate them into branches to enrich the inner cavity results.
(3) branching
Branching is an important measure to shape young trees and bear early fruits. When young trees cultivate the main and lateral branches, the direction of new branches is suitable, and the angle is small. From June to August, the branches are pulled according to the ideal angle and direction to make the branches grow as required. For branches that are not backbone branches and have a small angle but are relatively strong, pulling branches can promote the middle and lower buds to be full, which is beneficial to the formation of branches and fruit branches in the next year.