In order to avoid bearing too much fruit and pressing branches of walnut trees, the following points should be paid attention to:
I. Pest control
Larvae of walnut longicorn beetle, mulberry longicorn beetle, mulberry longicorn beetle, etc. When tunnels are drilled in cortex and xylem, the strength of branches decreases, and when there are many fruits, they are easy to break. After finding pests, we should actively control them:
Artificial hunting is directly caught during the adult occurrence period. You can also use lights to trap and kill at night.
Every year11-65438+February, the base of the trunk is painted white, and it is fully mixed with 5 kg of quicklime, 0.5 kg of sulfur powder, 0.25 kg of salt and 20 liters of water to prevent adults from laying eggs and kill newly hatched larvae.
Check the base of the trunk after 6-7 months of artificial egg killing, find out where the eggs are carved or black water flows out, dig out the harm with a knife, and kill the eggs or newly hatched larvae; It can also be hammered to kill eggs or newly hatched larvae.
When the larvae are found to have eaten into xylem by artificial hook killing, a small hook can be bent at the end of the thin wire and inserted into the wormhole to kill some larvae.
When the walnut tree is found to have feces discharged, all the feces near the wormhole are removed, and 80% dichlorvos emulsion or 200% phoxim emulsion is injected from the wormhole. You can also dip a cotton ball in 50% phoxim EC or 50% chlorpyrifos EC and stuff it into the wormhole. You can also insert a zinc phosphide cotton swab into the wormhole to smoke and kill the larvae, and you can also get good control effect by punching and injecting drugs.
Protect natural enemies and attract birds, such as woodpeckers.
Second, reasonable pruning.
Dense branches, cross branches and overlapping branches at the periphery of the crown should be drained or retracted in time. For some weak branches with insufficient illumination and more consumption than accumulation, they should be thinned out in time to meet the requirements of evacuation of peripheral branches and non-empty lumen.
By using strongly developed branches, the strong branches born in the middle or outside of the main and lateral branches can be removed, the strong branches can be removed, and the straight branches can be left flat, and the remaining developed branches can be gradually transformed into middle branches or branchlets.
Control long branches, control the use of long branches with inner cavities, and make the living parts suitable without affecting ventilation and light transmission. Generally, the head is longer, and it retracts at the weaker branches in the second year, and it is cultivated into smaller fruiting branches. The spacing between branches should be 60- 100 cm to facilitate ventilation and light transmission. For aging branches, they should be retracted and rejuvenated in time.