Prevention and remedial measures for Frost injury of Walnut

Walnut is one of our common nuts. Walnut likes light, cold tolerance and drought resistance, but the annual seedlings of young trees have high moisture and low cold resistance, freezing injury and early spring striping in winter or frost season, which seriously affect the growth and development of plants and cause plant death in serious cases. So how to prevent walnut frost injury? How can it be remedied? Let's take a look.

1. Preventive measures

1. Fertilization

Before July, nitrogen and potassium compound fertilizers are mainly applied, but after July, compound fertilizers based on phosphorus and potassium fertilizers are needed. In addition, trace elements such as calcium and boron are also applied, which are willing to promote the full maturity of branches and buds, thus enhancing the cold resistance of plants.

2. Watering

After the walnut blossoms and bears fruit, the precipitation is less, so it should be watered once at this time, and when it enters the rainy season, it is necessary to control the water to mature to ensure that the plant stops growing in time. Before freezing, it is necessary to pour frozen water once to increase soil moisture, which can slow down the decline of soil temperature and make it safe to survive the winter.

3. Proper pruning

The main purpose of young tree pruning is to shape and quickly form a crown, while the old tree pruning is to adjust the relationship between growth and fruit, so as to improve the yield and quality of walnut. However, from the point of view of preventing frost injury, in addition to routine autumn pruning, more attention should be paid to summer pruning, pruning some overgrown branches and close planting, increasing permeability and making branch and bud growth more robust.

4. Spraying protective agent

Before winter or early spring, the plant can be sprayed with cryoprotectant, which can improve the cold resistance of the plant, and the effect is better.

II. Remedial measures

After the beginning of spring, the branches killed by freezing injury should be trimmed off in time, and the wound after pruning should be smeared with medicament to prevent germs from invading and causing rot. in addition, after pruning, the management of fertilizer and water should be strengthened to restore the tree potential as soon as possible. Before planting germination, methyl topiramate or pubiqing emulsion should be sprayed comprehensively, which can play the role of sterilization and prevent the plant from being invaded by bacteria with low resistance. As for the rotten branches, the old skin can be cut off slightly, while the symptoms are severe and have rotted to the xylem, the scar can be removed along the periphery of the disease spot to make it fusiform, and the medicine can be applied to scrape off or burn the disease branch.

The above are walnut freeze injury prevention and remedial measures, hope to help you, want to know more related knowledge, please follow us.