The total number of chestnut trees planted in the past few years has gradually increased, and during the period of chestnut planting, it is also very easy to produce some insect pests, which are very harmful to the growth and development of chestnut and its production, in which the most common insect pests are chestnut weevil, chestnut moth, chestnut red spider, chestnut aphid, in which the chestnut red spider and chestnut aphid are the high incidence of the two kinds of insect pests in North China, which is very harmful to the development of the chestnut tree, and the development of the chestnut tree. The first one is the chestnut red spider and chestnut aphid.

Chestnut red spider: the original is to harm some broad-leaved trees, and then gradually began to harm the chestnut, oak, palm and these green plants, chestnut trees in North China often appear on the occurrence of, if the bugs and noctuid insects will inhale the sap of the chestnut tree leaves, chestnut red spider's leaves, will show a light white spot, the course of the more serious infestation of chestnut tree leaves will gradually fall off the initial stage, resulting in a poor plant growth. The growth and development of chestnut tree and its fruit production will also be jeopardized. The fruit grown by chestnut red spider will be small and light in color, which will be very harmful to the production and quality of chestnut.

Chestnut red spider's life habit: this kind of pest can happen 5--9 generations a year, laying eggs in the branches and trunks of the chestnut tree for the winter, especially in the branch and trunk buds and leaves around the first born, and the roots of the tree gaps, bifurcation area is more, chestnut red spider is very sensitive to the natural environment, occurring in the arid climate of the years, and on the other hand, it will occur less.

Chestnut red spider prevention: before the chestnut tree buds, apply 3--5Be oxidized lecithin to eliminate the wintering larvae, and after the insect pests occur, you can apply 1.8% avermectin emulsion 4000 times, 2.5% Huaguang fungus 800 times, 73% kefite 3000 times, 20% pyridaben wettable granule 3000 times, 5% bazhacarb suspending agent 2000--3000 times. 2000--3000 times liquid. Dosing should be delicate and thorough, and pay attention to the alternate application.

Chestnut aphid: also known as chestnut black aphid, alias putty worm, in the northern region of chestnut trees occur from time to time, this kind of insect pests in order to worm and noctuid clusters together, inhaling the branch young leaves sap damage, the occurrence of a piece of the chestnut tree for the growth and development of a greater damage can lead to the gradual decline of the plant, for the production of a greater harm.

Chestnut aphid habits: the larvae of this type of pest, will be in the roots of chestnut trees in the crevices of the winter, in the spring after the temperature rises oviposition into a wingless female aphid, clustered in the tips of chestnut trees, inhalation of sap, the temperature really warm, will be transferred to the leaves of the chestnut tree, and gradually clustered in the flowers, branch tips and other areas of injury, the gradual laying of eggs in the autumn over the winter, will lay larvae in the trunks of chestnut trees, the crevices, scars or shrubs. Cracks, tree scars or bushes, egg production is large, the damage is very serious.

Chestnut buds prevention: after the winter leaves fall, carry out scraping roots, with the effect of solving the larvae, after the temperature rises, the pests present, you can apply the drugs to carry out the application of drugs can be used: 10% acetamiprid wettable granules 4,000 times, 3% acetamiprid emulsifiable concentrate 2,000 times, EB-82 aphidic acid fungus 200 times, 20% of the perchlorothiazide 3,000 times. Or 20% permethrin 3000 times liquid.

These two commonly used chestnut tree insect pests, occurring more frequently in North China, for the growth and development of chestnut trees, is extremely harmful, but also in our daily management methods during the period, to do a good job of early detection, early prevention, will be removed from the insect pests, in order to get effective access.