How to prevent the fruit part of Chinese chestnut from moving out?

How to prevent the fruit part of Chinese chestnut from moving out?

Chinese chestnut has the habit of strong branches to bear fruit, while in general, the strong branches of trees are in the periphery of the crown, so the external fruit is formed. Young trees have few fruiting branches and low yield, while adult trees have thinner and thinner branches and lose their fruiting ability with the increase of branches, which is an important reason for the low yield of chestnut trees. In order to promote the growth of strong branches on the periphery of Chinese chestnut, clear chamber pruning was often used in Jizhou area of Tianjin, which led to more outward movement of the fruit, with all the fruit on the treetop and bald back. After years of production practice, the solutions are put forward as follows.

Pull branches, heavy truncation. Combined with the perennial fruiting branch group, if the fruiting part moves outward, the base is bald, the growth becomes weak, and there is little fruit, the better branch should be shrunk, the new branch group should be cultivated, and the robust fruiting mother branch should be produced. Pulling branches can also play the role of sending new branches and achieve three-dimensional results.

Wipe the buds. For each fruiting mother branch, there were 3-4 full buds in the upper part and 1-2 buds in the lower part. Remove the small buds and leave the big buds; if it is too dense, remove the medial buds and leave the lateral buds. It is necessary to master "go to the small and stay big; go to the secret and keep sparse; there is more on the outside and less in the interior, and more on the top and less on the bottom". After sprouting, nutrients are concentrated and grow well, which is beneficial to blossom and fruit setting.

Shu Xiong. The male flower of Castanea mollissima is several times more than the female flower and consumes a lot of nutrients. The excess male flower should be removed, and the best effect is when the male inflorescence of Castanea mollissima grows 1~2cm. It should be divided as it grows. After more than 10 days, mixed male and female inflorescences can grow, with male flowers above and female flowers below, 2 or 3 male flowers left for pollination and the rest thinned.

Pick the heart in front of the fruit. After the mixed flower bud grows, the new shoot that continues to grow in front is the fruit front shoot, leaving 3 or 4 leaves to pick the heart, which can increase the fruit setting rate and reduce the canopy.

Artificial pollination. The varieties with large grains, good quality, early maturity and high affinity were selected as pollination trees. the male flowers were picked when the male inflorescence changed from green to yellow, and it was better to pick them before 8 o'clock in the morning. Spread the collected male inflorescence on glossy paper and place it in a dry, ventilated and dust-free place. Turn it several times a day, and pollen will be dispersed in 24 hours to collect pollen. When the female flower stigma begins to bifurcate, a point can be taken, as the middle of a female flower stigma matures first, it should be given more than a few times. The effect of teaching with a brush is better.

Shrunk. Too much chestnut canopy not only affects the development of the tree, but also causes the age. When the diameter of chestnut canopy reaches 0.5cm, the stigma will dry up (probably in late July). It is beneficial to reduce the empty canopy by removing too much chestnut canopy and concentrating nutrients. The standard of keeping canopy is as follows: strong branch (30~35cm), single branch (2%), middle branch (long 20~30cm), and weak branch (below 20cm). No matter the strong, medium or weak branches, only one canopy is left on the same node. When the canopy is sparse, the young and prosperous trees are less sparse, the adult weak branches are more sparse, the outer and upper parts are less sparse, and the inner chamber and the lower part of the crown are more sparse.