How to effectively control pests and diseases in garden nurseries overwintering

In winter, the vast majority of plant diseases and pests will enter a dormant state, at this time, the incubation position of pests and diseases is relatively concentrated, the cycle is relatively long, and the life is relatively weak, just like the need to go through a small level, and the number of people who can naturally pass the "level" will be greatly reduced. If effective prevention is carried out at this time, it will save time and effort and cost, and the effect will be outstanding, and it will play a multiplier effect with half the effort.

As a garden nursery for economic benefits, not all pests and diseases are suitable for winter prevention, and should be determined according to the characteristics of various pests and diseases. So which ones are good for winter prevention? What are its corresponding prevention and control measures?

1. Spray the trunk with stone sulfur compound or Bordeaux liquid

This is the most common winter maintenance and management measures for gardens, which is highly efficient, low cost and effective, and is widely used in the production and maintenance of seedlings, orchards, forestry and so on.

Among them, the stone sulfur compound is more popular due to its low cost, wide prevention and control defense (disease and insect pest killing), especially the crystal stone sulfur compound that has been chelated, which is very convenient to use. Bordeaux liquid is generally only used for disease prevention.

The following pests and diseases are suitable for winter stone spray sulfur compound or Bordeaux liquid control:

A. Trunk and branch diseases

Common rot diseases (such as Xifu begonia rot disease), ulcer disease (such as no disease canker disease), abdominal breakdown (such as woolly poplar broken abdomen), plaster disease (such as plum blossom plaster disease) and so on. The harm of such diseases is deep, and it is difficult for conventional fungicides to completely kill pathogenic bacteria, so it is difficult to cure. However, the disease activity and reproductive ability in the dormant period are weak, and the prevention at this time can achieve more ideal results.

B. Insect pests that overwinter on deciduous trunks (branches) with eggs or insects

Such as wax nymphs (eggs or insects), red spiders (adults), autumn four-veined cotton aphids (eggs), etc., these pests or insect eggs are in the tree in winter, and can be destroyed by stone sulfur compounds to eliminate their wintering insects or eggs to reduce the number of insect populations in the coming year.

In addition, in winter, due to the lack of leaf shade and the overlap with generations, the source of insects can be completely removed. Such as the beech tree autumn four veins of cotton aphid, the growing season by the insect gall protection, the general drug is difficult to reach, while the branches and leaves are dense, the amount of medication is also very high, and after the fall of leaves, as long as a small amount of stone sulfur mixture, you can kill the insect eggs lurking in the trunk, the next year basically do not need to control.

C. Frequent diseases of deciduous trees

This requires the satisfaction of two conditions, namely deciduous trees and frequent occurrence, evergreen trees due to winter still have leaves, high concentrations of stone sulfur compound or Bordeaux liquid is easy to cause drug damage, need to be used with caution.

Common susceptible diseases such as weeping begonia brown spot disease, cherry blossom brown spot perforation disease, Xifu begonia leaf spot disease, etc. These diseases are almost certain to occur and need to be treated multiple times during the growing season. In winter, because there are still a large number of residual bacteria on the tree, killing the residual bacteria with stone sulfur compound or Bordeaux liquid can significantly reduce the incidence of diseases in the next year, which is equivalent to multiple drugs in the growing season.

Winter stone sulfur compound or Bordeaux liquid use method: 45% crystalline stone sulfur compound 30-50 times or chelated stone sulfur compound 3-5bé, equal or half-volume Bordeaux liquid.

2. Paint the trunk white

The trunk is coated with white insecticide and sterilization thoroughly, which can effectively control the insect pests and stubborn diseases in the trunk, and can also prevent frost and sun, which is an important task for the winter maintenance of road greening seedlings. However, due to the high cost of whitening efficiency, it is difficult to promote and apply a large area in nursery production, and this method can be used for some trunks with serious diseases and insect pests, such as camphor with severe abdominal disease and camellia with rotting disease.

Configuration method: Can be used copper sulfate, quicklime, water at 1:20:60 or with sulfur powder, quicklime, water, salt, animal oil at 20:10:100:2:1 configuration.

However, this kind of whitening has a short shelf life, poor adhesion, and lime alkalinity, industrial salt causes soil salinization, long-term use will pollute the soil, affecting the growth of seedlings. In order to solve the many drawbacks of traditional whitening agents, after 5 years of technical research, The Plant Protection of Lain Ping'an Garden in Henan Province has finally developed an environmentally friendly trunk whitening agent - a new generation of White Doctor.

3. Thinning

Cutting off diseased and insect branches is of great significance for controlling the harm of pests and diseases in the coming year. The following are suitable for pruning in winter:

A. Branches where the pest has been mothed into the shoots and overwintered in the shoots

Common borer pests in our nurseries include stem bees, curl moths, borer moths and other borer heartworms, and some wood beetle moths, celestial cattle, etc., such as wood beetle moths that enter the eucommia stalks and overwinter in the stalks.

Cutting off these insect branches and destroying them intensively will greatly reduce the source of insects in the coming year.

B. Severe branches of wax bugs

Wax bugs are densely packed with branches that can be pruned properly. Cutting off the affected branches can reduce the source of insects and increase ventilation light, which is not conducive to the growth of wax bugs, and through freezing, the insect infestation will be greatly reduced in the coming year.

C. There are blight branches

Cutting off the branches with disease and cutting off the disease infection for many years will greatly facilitate the growth of seedlings and reduce the recurrence of diseases.

D. Moth into the branches of the insect eggs

There are many pests that lay eggs on trees, and it is impossible to prune branches because of eggs, but pests such as wax cicadas and grasshoppers lay eggs in branches and can cause branches to die, so they should be pruned.

4. Eliminate overwintering pests

For some stinging pests that do not migrate well and overwinter in trees with adult insects, completely killing the overwintering insects is equivalent to cutting off the transmission chain from the first to the second year, and the effect will be very prominent, far better than the control effect of the growing season. This method can be used for pest mites with great harm and strong reproductive ability (such as camellia leafhoppers and osmanthus red spiders). For example, the growing season of camellia leafhoppers can occur for more than 10 generations a year, and the growing season requires multiple medications, but if it can be completely cleared before wintering in November and before spawning in March (trunk leaves are fully and thoroughly sprayed), there is basically no need to prevent it throughout the year.

5. Soil insecticide or ploughing

The use of some old and mature larvae of the pest to make a cocoon overwintering habit, before the insect has landed or just landed, spray or sprinkle soil insecticide on the ground, you can kill the ground pest.

In garden production, the following characteristics must be met before this method can be used: a, the harm is large; b, the overwintering generation is neat; c, the ground is concentrated in the cocoon part. Pests that are scattered on the ground, overwintering, or less harmful are not suitable for this method. For example, the peak of the camphor leaf of the severed head camphor is more harmful, and the landing site is basically only around the canopy of the trunk, and the ground insecticidal effect is relatively good. The overwintering pests in the soil where the red edge lamp moth and the twill moth are not concentrated are not suitable for ground killing.

In addition, ploughing the soil in winter can freeze to death pests, but due to the difficulty of the work and the high labor cost, it is not suitable for the production of large-scale garden nurseries. However, for those underground pests that are particularly harmful and the damage sites are very concentrated, this method can also be used to control overwintering pests, such as safflower grub damage, ploughing the soil and applying soil insecticides can kill a large number of pests.

6. Control the trees to overwinter

Some pests have to climb down the ground through the main pole to overwinter (such as the apocytope nocturnal moth), and we only need to apply a ring of sticky shellac or tie a circle of sticky worm tape to the trunk before descending the tree, and the pest cannot overwinter.

In short, if the overwintering of diseases and insect pests can be effectively controlled, the harm caused by diseases and insect pests will be greatly reduced in the coming year, and the workload of disease prevention and pest control in the growing season will be greatly reduced, but in terms of practical application, continuous research and exploration are still needed.