Peach trees that are dormant in winter are prone to frostbite. How should they be treated?

When it comes to planting fruit trees, especially peach trees, fruit farmers have both joy and worry. The worry is that high yields are limited by natural climate conditions. In recent years, due to abnormal climate change (it can be said that it is abnormal every year), many peach tree planting areas often suffer from winter freeze damage and late spring cold damage before and after the flowering period, causing losses to the majority of fruit farmers. 1. Let’s first look at the low-temperature tolerance of major fruit trees and the critical values ??of organ freezing

The cold resistance of different tree species and varieties is determined by genetic factors and biological characteristics formed by long-term phylogeny.

The fact that peach trees can endure does not mean that they are safe and sound at this temperature. In fact, most of them will be frozen at this temperature. What do you think?

It is crucial to understand the data and be aware of it. 2. Symptoms of freeze damage to peach trees

1. Freeze damage to flower buds

Frost damage to peach trees is closely related to the period of low temperature, the duration of low temperature, and the range of temperature changes. . During the dormant period of peach trees in winter, the flower buds have weak cold resistance and are easily frozen when encountering low temperatures. After the flower buds are frozen, the stamens inside will turn black when cut, they will not germinate in spring or the germination rate is very low, and the flower buds will gradually dry up, die and fall off. A small number of flower buds that are frozen will have a certain impact on the current year's yield, and tree growth can be restored that year; when a large number of flower buds are severely frozen, the current year's yield will be severely reduced; when all the flower buds are frozen, there will be no yield that year. The deeper and more completely the flower buds are differentiated during the winter, the lower their cold resistance. In other words, the better we look at it, the bigger it will suffer first.

This was taken in spring, blooming soon, with frost

2. Freeze damage to branches:

Mature branches have the cambium layer that is most resistant to cold, and the bark Among the layers, xylem and pith are the least resistant to cold. When the temperature is low in winter, or when the growth of branches is weak that year, or when nitrogen fertilizer is applied too much and the branches are not full, the branches will be damaged by freezing in winter. In severe years, the frozen branches will change color and gradually dry up and die, and the flower buds on them will also Death, resulting in serious production reduction, this probability rarely occurs in Shandong, but it cannot be ruled out that it may occur in years.

Investigating the frost damage of seedling branches at Guonongle Base in Xuezhuang Town, Feixian County, the pith turned brown first

3. Freeze damage to trunk branches:

Winter When the temperature is too low, it will cause freeze damage to the main trunk, main branches and other backbone branches. This year, the cortex of the backbone branches above the grafting interface was frozen and turned brown, and some rotted and smelled like lees. Freeze damage to backbone branches will not only have a serious impact on the yield of the year, but also seriously damage the tree skeleton, affecting the yield for many years. Of course, although serious cases occur in a few places, attention must be paid to them. Even though the tree will be damaged in the next spring It has the ability to heal and recover itself, and once it occurs, it will also cause the tree to become weak.

The main trunk of the peach tree is frozen and the cortex turns brown

4. Late frost damage during the flowering period:

Peach trees bud and bloom early in spring and are most vulnerable to late frost damage. Frost and low temperatures during the flowering period will cause flowers and fruits to drop, resulting in reduced yields. In severe cases, there will be no yield for the year. Care must also be taken to prevent frost damage in the greenhouse.

There is frost during the flowering period, causing the flower buds to be frozen

5. Young trees are dried out due to freeze and drought:

Newly planted 1-3 year old saplings , the phenomenon of water loss, wrinkled skin and dryness occurs in winter and spring, commonly known as "strips". The reason why freeze drought occurs is that due to freezing of soil moisture or low temperatures during winter and spring, the root system cannot or rarely absorbs water, while the above-ground branches evaporate strongly, causing plants to suffer from severe water loss.

We will do some investigations after freezing damage occurs, and issue early warnings every year to inform fruit farmers. 3. Prevention of freezing damage to peach trees and post-freezing damage reduction measures

1. Flower buds freezing damage: Freezing damage to flower buds will reduce the yield of the year. Care should be taken to control the growth potential of the tree and the differentiation of flower buds to avoid excessive growth by applying nitrogen fertilizer in summer and autumn. When pruning in winter, keep more flower buds appropriately.

Prune in winter to keep more flower buds according to the freezing situation

2. Frost damage to branches? Prune appropriately and in time according to the degree of frost damage, cut off the dead parts, and perform reasonable summer pruning on the new shoots. , strengthen the prevention and control of pests and diseases, and protect the leaves to improve photosynthetic efficiency, accumulate more nutrients, promote branch maturity, cultivate new fruit-bearing branch groups, promote flower bud differentiation, and lay the foundation for flowering and fruiting next year.

After the seedling branches are frozen, they are planted in a greenhouse to test their branching ability.

After the seedling branches are frozen, they are planted in a greenhouse to test their branching ability. The pith turns brown, and the cambium layer is not affected. The germination and growth are normal.

3. Freeze damage to the backbone branches? Freeze damage to the backbone branches causes great damage to the tree body. When the main trunk is severely damaged by frost damage, it is necessary to cut down and rebuild the garden or take the measure of grafting and replacement. Generally, the grafting joint is susceptible to freezing. , rootstocks have strong frost resistance and are generally not affected by frost damage. In addition, it is necessary to wait until spring germination to confirm that it has not sprouted and cannot recover due to freezing before taking measures to replace the head. This requires that during winter pruning, scions of excellent varieties should be selected and stored in the sand for spring. It should be used during grafting; when some backbone branches such as main side branches are frozen and die, they can be sawed off from the frozen parts, and new backbone branches can be cultivated after new branches are sprouted. Sawed dead branches should be cleaned up in time.

The basic roots and necks of the backbone branches are frozen, so it is necessary to consider rebuilding the orchard

The frozen orchard must be plowed to loosen the soil as soon as possible, and protective measures must be taken for the saw edges. Use 3-5 degrees Baume lime sulfur mixture to smear the wound, and whiten the trunk in winter; pay attention to fertilization and irrigation before and after germination to promote the recovery of tree vigor.

Peach trees that have been frozen will be infected with a variety of diseases and insect pests, such as rot, gum disease, etc. They must be scraped and cured in time, and fungicides such as Diphen and Methylamine must be applied.

4. What is the harm caused by late spring cold during the flowering period? Peach trees bloom early and are extremely susceptible to the damage of late frost. Frost damage during the late flowering period will seriously affect the results. Before flowering, you should keep abreast of weather changes and take timely measures before frost occurs. The following measures can be taken: (1) Delay germination, such as using early spring irrigation, whitening tree trunks and other measures to delay flower bud germination; (2) Improve the microclimate of the orchard: In the evening before frost, prepare firewood, sawdust and other materials, when the temperature drops to When peach trees are frozen at freezing temperatures, firewood is ignited for smoke to increase the temperature in the orchard. 4-5 ignition points can be set up at the upwind of each acre of land; this year, in order to reduce haze weather, the environmental protection department does not allow cigarettes and fires to be lit. , you can spray water on the orchard to prevent freezing damage and the effect is good (3) Strengthen comprehensive cultivation and management technology, use more organic fertilizers to enhance tree vigor.

This is a sign of freezing damage in winter and entering the growing season

5. Newly planted saplings: Strengthen management, advance and control, strengthen fertilizer and water management in the early stage of growth, and strengthen fertilizer and water management in the later stage of growth. Controlling the supply of fertilizer and water to promote the maturity and aging of branches is an important measure to improve cold resistance. At the same time, we must prevent and control the occurrence of pests and diseases, and take protective measures such as covering the trunks with soil and wrapping them during the winter.

It is necessary to raise anti-freeze awareness from the beginning of the new garden

6. Choose a suitable garden site: When building a new peach garden, you should try your best to choose a sunny place with leeward direction, and avoid low or shady terrain. Build a garden. Years of investigation have found that frost damage is significantly reduced in higher locations, and location selection is critical.

This is a peach orchard established by fruit farmers in Fei County. It has been fertilized in autumn and watered with frozen water