Key Management Techniques for Fruit Trees After Flood Disasters

Since late July, many places in Hebei Province have experienced continuous heavy rainfall, with consecutive rainy weather in Handan, Xingtai, Shijiazhuang and many other places. In some areas, daily rainfall reached over 100 mm, and some areas have already experienced flood disasters. Heavy rainfall can cause waterlogging in orchards, resulting in fruit drop, yellowing leaves, and weakened tree vigor. Prolonged waterlogging can severely cause tree death. Continuous rainy weather, due to high temperature and high humidity conditions, can also easily trigger major outbreaks of diseases and pests, seriously affecting the yield and quality of fruit trees. This kind of weather often occurs during the flood season, so we must pay attention to orchard management during the flood season and promptly carry out the following work.

I. Drain Water Promptly

Many orchards in our province, due to years of drought, have not paid attention to drainage work and have no drainage equipment. Especially some orchards in low-lying areas often suffer waterlogging damage after heavy rainfall. It is best to dig drainage ditches in advance before the flood season arrives, so that accumulated water can be drained after heavy rain. If the terrain is low, drainage pits should be dug. Orchards in low-lying areas should prepare pumping equipment, and when necessary, use water pumps to drain water. After flood disasters occur, various measures should be taken promptly to drain water and prevent waterlogging damage to fruit trees. Especially for tree species with poor waterlogging resistance such as peach and cherry, drainage should be carried out even more promptly.

II. Do a Good Job in Fruit Tree Disease Control

The high temperature and high humidity weather after continuous heavy rainfall is most suitable for the growth and reproduction of various fruit tree pathogens. In addition, waterlogging leads to reduced tree resistance, making it very easy for various diseases to break out. Therefore, after continuous heavy rainfall, disease control work for fruit trees must be strengthened. At the same time, the following principles should be grasped when spraying:

1. Spray promptly for control after the weather clears. Many diseases develop rapidly under high temperature and high humidity environments, so spraying should be carried out promptly after the weather clears. If you wait until diseases show symptoms before controlling them, it is often because control was not timely that diseases break out severely.

2. Spraying should focus on systemic fungicides, supplemented by protective fungicides. After rain, systemic fungicides can remove pathogens that were previously latent in young fruit and leaves, and in the rainy season they can be quickly absorbed by fruit trees, take effect, and be prevented from being washed away by rain. If spraying before rainfall, protective fungicides can be used.

3. Pay attention to alternating the use of multiple fungicides to prevent various fruit tree pathogens from developing resistance and to ensure spraying quality.

4. Use Bordeaux mixture as much as possible. Bordeaux mixture not only does not cause resistance, but also has strong adhesion and resists rain erosion, making it extremely suitable for spraying during the flood season. When conditions are suitable, it is recommended to use Bordeaux mixture as the main spray as much as possible. For tree species and varieties prone to phytotoxicity, a double-strength Bordeaux mixture should be used. For tree species in the harvest period, conventional fungicides can be sprayed.

5. Pay attention to spraying quality. When spraying, atomization should be good, and the spray should be uniform, thorough, and meticulous to ensure quality.

III. Do a Good Job in Fruit Tree Pest Control

After fruit trees suffer flood disasters, control of various pests should also be done well to ensure normal growth of leaves and fruit. Especially for fruit trees cultivated with bagging, control of "bag-entering pests" must be done well. Once "bag-entering pests" enter the bags, they are extremely difficult to control.

IV. Clean Up the Orchard Promptly and Straighten Tree Bodies

Heavy rainfall is often accompanied by strong winds, causing fruit trees to be blown down and large branches to break. Branches broken by strong winds should be promptly cut or sawed off and cleared out of the orchard to prevent dead branches and the triggering of pests and diseases. At the same time, fallen fruit and fallen leaves blown down by strong winds should be promptly cleared out of the orchard. For fruit trees blown crooked or even blown down by strong winds, corresponding measures such as propping, pulling, and bracing should be taken to straighten the tree bodies.

V. Do a Good Job in Orchard Soil Management

1. The flood season is also the rapid fruit growth period for most fruit trees. After flood disasters occur, fruit trees should be topdressed promptly to supplement various elements such as nitrogen, phosphorus, and potassium, provide the various nutrients needed for fruit growth, and ensure the fruit grows large.

2. Orchards with silt should have the silt promptly cleared after drainage, especially the silt at the root crown of fruit trees should be removed as soon as possible to ensure the tree bodies return to normal growth as quickly as possible. When conditions permit, cultivate or deep plow promptly to make the soil loose and increase aeration, so as to facilitate normal root growth.

3. Various weeds in the orchard should be promptly removed to facilitate ventilation and light penetration and save nutrients.

VI. Do a Good Job in Summer Pruning and Adjust Tree Growth Vigor

During the flood season, there is much rain and high temperatures, and tree bodies are prone to excessive vegetative growth, with rampant growth of branches and leaves competing for large amounts of nutrients, affecting fruit size and quality. During the flood season, summer pruning should be carried out promptly, mainly thinning or pinching off rampant shoots to reduce nutrient consumption, concentrate nutrients for fruit growth, help flower bud formation, and use ventilation and light penetration to reduce the occurrence of pests and diseases. For different tree species and varieties, the number of summer pruning times varies according to tree growth vigor and the amount of branches and leaves. Generally, apples, pears, etc. can be pruned 1 to 2 times, while peaches, grapes, etc. can be pruned 2 to 3 times.