Do a good job of shaping and pruning mature trees to achieve the effect of controlling prosperity. The methods are as follows:
1, the purpose and importance of pruning mature trees
The pruning of young trees is the foundation, while the pruning of mature trees is the key, because macadamia nuts are boring fruits, and flowers and fruits are mainly planted on mature branches in the crown. If the mature trees are well trimmed, the fruiting mother branches can be extracted from all parts of the crown, making full use of the space, increasing the fruiting surface and increasing the yield. Australian nut mature tree.
2. Specific methods of pruning adult trees.
The pruning of adult trees mainly includes the cultivation and pruning of fruiting mother branches, the control and utilization of long branches, the pruning of branch groups, and the retraction and renewal of backbone side branches, each of which is essential.
(1), culture and pruning of fruiting mother branches.
Most of the 2-3-year-old branches growing in the crown of macadamia nut are fruiting mother branches. The cultivation method is as follows: when the primary branch on the trunk grows to about 30-35 cm, coring is carried out; After the first branch is cut off, the upper three axillary buds germinate and grow into the second branch. When it grows to 3-4 nodes, only one branch will continue to grow into the main branch, and the other two branches will nucleate at 3 or 4 nodes. When the terminal bud of the main branch is about 30-35cm long from the last branch point, the branch is picked to promote its branch, and the method of retaining the branch is the same as above. According to this method, high-order branches are carried out, and the spatial orientations of branches at all levels are staggered in the crown. 2-3 fruiting mother branches can be left on each 2-year-old branch, and the other branches with unreasonable distribution should be properly thinned out. Don't cut off the main branches and weak branches at all levels of the trunk without causing great interference and concealment, because such branches are also fruit-bearing branches.
(2) Control and utilization of long branches
As a result, the lateral branches of the trunk at all levels of the tree may sprout branches. If left unchecked, it will disturb the tree shape and consume nutrients. Therefore, reasonable selection, control and utilization should be made, and branch groups and regeneration branches should be cultivated. When selecting and retaining long branches, we should pay attention to the strength, position and direction of the branches. Generally speaking, the long branches with poor growth should not be cut short, and the long branches with strong growth should be combined with pinching in summer, pulling branches in winter and cutting short to promote their branches and leave horizontal oblique branches. After 2-3 years, the treated tendrils can form flower buds. When pruning, in order to ventilate the tree, skylights are often used, that is, the top of the trunk of the plant is cut off to let the light enter the tree from the top. This light transmission is very short, and the axillary bud germination ability of macadamia nuts is very strong. About 10 day after stem cutting, 3-8 buds germinated under the cross section. These axillary buds germinate rapidly and form long branches. Bundles of branches grow straight to the ground, and the branches at the top of the plant are dense, which can be improved by thinning and pulling branches.
(3) After many years of fruiting, the pruning branches of the branch group gradually weaken their growth and fruit-bearing ability, so they should be shrunk and rejuvenated. If there is no branch at the base of the fruiting branch, a short pile of about 4cm can be left to make the branch group retract, make the dormant bud at the base sprout new shoots, and then cultivate into a new branch group; If there are long branches at the base of fruiting branches, the long branches can be kept, so that the branches can be retracted and shortened, and the new shoots can be cultivated into new branches.
(4) Retraction and renewal of trunk side branches When the growth of trunk side branches is weak, the branches should be renewed in time; In order to avoid the yield loss caused by the retraction of trunk side branches, the updated branches should be cultivated in the lower part of trunk side branches in advance. When the updated branches have begun to form good fruiting mother branches and bear a large number of fruits, all the original weak branches should be retracted. When taking back the big branches, the kerf should not be too close to the updated branches. It is best to leave a short pile about 5 cm long above the updated branches.