In a year, fruit trees should be pruned in late summer and early autumn (from mid-August to mid-September). During this period, the branches were soft and plastic, so the angle of the branches could be opened or the extension direction of the branches could be changed according to the requirements of trees modeling. It can improve the lighting conditions of fruit trees, increase the nutrients synthesized by photosynthesis and accumulate more nutrients; It can control the growth of new shoots and enrich the bud growth in the middle and lower branches. In the second spring, the growth of budding branches is more balanced, which can increase the number of short branches and form short fruit branches, which has a good effect of slowing down the trend and promoting flowers. Therefore, it is best for apple trees to branch and open in August. The effect of pruning in May is not as good as that in August.
How to pull out the branches of apple trees?
First, the method of toothpick pulling branches
1. Toothpick brace angle and branch opening angle. 1. When the new shoot grows to 20-25 cm, spread it between the new shoot and the central stem at a horizontal angle with a toothpick; Second, when the new shoots grow to the required length, use the branch pulling rope (nylon grass, rope, branch puller) to pull the branches, flatten them and straighten them, and do not arch them.
2. The length of new shoots depends on the planting method, planting density and cultivated varieties. The self-rootstock double-dwarf cultivation mode of close-planting orchard (120 plants/mu or more) is short branches, and then branches are pulled out when they grow to 65 ~ 70 cm; When the density of dwarf intermediate stock cultivation mode is about 83 plants/mu, the long branches grow to 45 ~ 55 cm, and then pull out.
Second, the branch pulling period
1. toothpick opening angle time. It must be carried out when the new branches grow to 20 ~ 25 cm, when the new branches have entered semi-lignification, which is convenient for operation. Shaanxi is usually from May 15 to June 5.
It's time to pull the waist corner with a rope. Can be carried out during the whole growth period. Generally, 1 ~ 2-year-old branches should be pulled out in August-September, when the branches grow fully and are easy to be fixed after being pulled out. There are many buds in the spring of the next year and the tree shape is moderate. Branches over 3 years old should be pulled out from spring to mid-May after flowering. At this time, the branches are soft, easy to open, the wound heals quickly, and there are fewer stripes on the back.
3. Branch opening angle time. Generally, it is carried out in the late growth stage, that is, if the branches are not leveled or pulled out in place, they will be pulled out again. Pull with a rope or hang something on a branch.
Third, the branch pulling requirements
1. Determine the angle according to the growth potential. Branches have strong growth potential and large pulling angle; The growth potential of branches is weak, and the angle of branch pulling should be small. For Fuji varieties that are difficult to blossom and grow vigorously, the main branch angle should be pulled to 1 10 ~ 120, and the auxiliary branches should be pulled down to make them blossom and bear fruit early.
2. Determine the angle according to the density. In orchards with high planting density, the main branches are pulled to110 ~120; In orchards with low planting density, the main branches are pulled to 90 ~ 100.
According to the tree. Spindle-shaped main branches are pulled to110 ~120; The improved spindle-shaped main branch (base) is drawn to 90 ~ 100, and the middle-upper main branch is drawn to 100 ~ 120.
4. Pull branches according to varieties. Fuji110 ~120; Gala 80 ~ 90, Qin Guan 80 ~ 90.
Fourth, matters needing attention
1. Starting from young trees, when the annual branches grow to 20 ~ 25 cm, use toothpicks to open the base angle, which is generally about 90. When the branches grow to the required length, pull them to the required angle.
2. Pull all the bottom corners, waist corners and sharp corners of the branches in place, and the branches that are pulled out should be smooth and straight, not bow-shaped. The big branches are drooping, the middle branches are horizontal, and the branchlets cannot be pulled.
3. When pulling branches to prevent strangulation, untie them in time, and tie the rope to your mouth, not your mouth.
4. The branches should be evenly distributed on the central trunk, and the upper and lower branches should be empty, reasonably distributed and patchwork, and cannot overlap and cross.
5. For branches that need to change direction, buried piles should be fixed on the ground when pulling out branches. Buried piles must be strong, the pegs used should not be too short, and they should be nailed obliquely into the ground to ensure that the branches can be fixed for 3 ~ 4 months.
6. It is impossible to pull out the branches at once. Due to the top advantage of branch growth, it is necessary to constantly adjust the branch pulling position to ensure that the branch is pulled to the required angle.
7. Resolutely do not tie several branches together and pull them down, but fix them one by one, so that they can fully occupy space, be even and reasonable, and let the branches see the light.
8. You can't just pull down the branches without pulling up the branches. Both the upper branch and the lower branch should be pulled in place. We should deal with the relationship between individuals and groups when pulling branches.