Why whitewash tree trunks in winter?

Trees and fruit trees in parks, campuses, roads, and gardens tend to paint the lower part of their trunks white in winter. Why is that?

First, we have to figure out what the white stuff is. The main ingredient of the whitening agent used to whiten the lower part of the trunk is lime milk, as well as salt, soybean flour, and stone sulfur mixture. Here's how it's made:

Add water to them in a certain proportion, stir until even, and finally add a small amount of alkaline or neutral pesticides to enhance the insecticidal effect.

What is the effect of whitening agent on trees in winter? Winter weather is cold, and if we suddenly go outside after spending some time in an air-conditioned house, we will feel particularly cold outside. If you are outside all the time, the feeling of cold is not as strong as when it first came out.

Many people get frostbite on their hands and feet, often because they wash their hands and feet with cold water, or cold hands and feet with hot water, or roast cold hands and feet on fire. If we take a cold shower, first rub it with a small amount of cold water to make the hands and feet slowly cool and cold; Before washing hot water, rub your hands and feet, and rub your hands and feet with a small amount of hot water to warm them slowly; Before roasting the fire, slowly approach the fire from far to near, so that our hands and feet have a slow adaptation process from cold to hot or from hot to cold, which can greatly reduce and avoid the formation of chilblains. Plants are coated with whitening agent in winter, on the one hand, to prevent cold and frost damage, and on the other hand, to prevent pests and diseases.

Why can plant whitening prevent cold damage, frost damage, and pests and diseases? Winter weather is cold, however, it is always much warmer during the day when the sun comes out. So, we love to bask in the sun in winter.

However, plants are not as comfortable in the sun as we are in the sun. After we bask in the sun, we can hide in the bed at night when there is no sun, no matter how cold the plant is, it is still in the original place, so that it is hot during the day and cold at night, and the difference between hot and cold is very large, and the plant is the most vulnerable, more serious than our chilblains. The plant is white, and the white can reflect the sunlight and various radiation during the day, avoid the temperature in the plant from being too high, greatly weaken the temperature difference between day and night, and avoid the plant from being damaged by sudden temperature change.

At the same time, the whitening agent has a thermal insulation effect, just like our hands and face apply antifreeze and skin cream. In addition, in the late autumn and early winter, many insects like to lay eggs in the cracks of old bark for the winter, and the whitening agent has a killing effect on many pests.

Pest control. The main material for brushing the trunk in winter is lime, and the part of the trunk about one meter above the ground can be whitened to reduce the gnawing of insects and ants on the trunk and prevent the tree from dying in winter.

In fact, the white "dye" is lime water, which can be used to whiten the trunk to kill bacteria and insects, to ensure the healthy growth of trees in the spring of the next year, in addition, it can also keep the trees warm and prevent frostbite due to the contrast between hot summer and cool winter.

A: I remember our teacher told us that applying lime water to trees in winter has the following functions: 1Because lime water has a bactericidal effect, it can kill the insects inside the tree.

2.You can prevent insects from climbing up the tree. 3.

Applying lime water to the tree can also protect against freezing.

On the one hand, whitening the trunk can help protect the trees from the cold and prevent them from frostbite in winter. Lime water, on the other hand, can kill insects and therefore help protect trees from pests.

The thing used to paint the lower part of the trunk white is called whitening agent, and the main ingredient of whitening agent is lime milk, as well as salt, soybean flour, and stone sulfur mixture. There are two main purposes for applying whitening agent to plants in winter: on the one hand, to prevent cold and frost, and on the other hand, to prevent pests and diseases.

1.Lime water has a certain bactericidal and insecticidal effect, which can kill some overwintering fungi, bacteria and pests parasitic on the trunk; 2。Pests generally prefer black, dirty places, and if you apply white lime water to the trunk of the tree, the pest will not climb the tree; 3.

The trunk is painted white, which is quite coated with a protective layer, which can play a role in anti-freezing; 4.In the summer heat, when exposed to high temperatures and strong sunlight, the lime on the trunk reflects sunlight and can play a role in preventing sunburn.

There are many ways to keep trees warm in winter, and the common one is whitening, which is a mixture of quicklime and stone sulfur mixture on the trunk to reduce frost damage. Or use mulching, where the young tree is wrapped in straw and covered with a woven bag. There is also the bandaging method, which is used to keep the soil at the bottom of the trunk and wrap the trunk with wheat straw or plastic sheeting, which can also well avoid frost damage.

Which trees need to be protected from the cold?

All types of fruit trees need to be protected from the cold. In addition, evergreen trees, hedges, etc., such as black pine, big-leaved boxwood, privet hedges, newly planted plants, precious plants, and frost-intolerant plants, also need to be protected from cold.

When to take precautions against the cold?

Winterization measures are generally taken from the end of October to the beginning of November, when most plants go dormant until early frost or snowfall at the latest. The dismantling time of cold protection measures is not earlier than the late frost, that is, the spring cold.

The white paint brushed on the tree is generally limestone, not paint, the ingredients are relatively simple, not very complicated, and you can use 10 copiesQuicklime, 2 copiesStone sulfur mixture, 2 copiesEdible saltMix 2 parts of clay, and then add water to it, so that the stirring and mixing can be successfully prepared.

When brushing on the tree, it is best to brush it twice, so that it can have a good effect, the effect of one time is not very obvious, the first time after the fruit tree has fallen leaves, and the second time in early spring.

Precautions for the use of whitening agent.

1. When using, the whitening agent should be fully stirred evenly, especially the lime must be fully matured, and it must not contain particles, otherwise it will burn the tree, and the lime milk can be filtered if necessary.

to remove residue and other particulate debris.

2. Before smearing, carefully check whether the tree body has dry moth pests, and if you find that the cavities should be plugged with a cotton swab, and then whitened after sealing the mud.

3. The height of the trunk should be 1 meter at the lower part of the trunk, which can be grasped according to the height and thickness of the tree, and attention should be paid to keeping the height of the white coating consistent to facilitate the appearance.

The white substance brushed to the trunk in winter is lime water, which is generally mixed with quicklime, stone sulfur mixture, salt, clay, water, etc., which has the effect of killing various pests and eggs, and can prevent the bark from cracking due to the excessive temperature difference between day and night, which is conducive to the safe wintering of plants.

The white substance to be brushed on the trunk in winter is lime water, which is generally mixed with quicklime, stone sulfur mixture, salt, and clay in a ratio of five to one to one, and diluted with water to obtain a water solvent, and when brushing on the trunk, it needs to be brushed two to three times.

Brushing white solvent on the trunk of trees in winter can not only kill various pests and eggs in the cracks of the bark, prevent the occurrence of pests and diseases from the root, but also prevent the bark from cracking due to the excessive temperature difference between day and night, which is conducive to the safe wintering of plants.

The winter climate is very cold, and it is necessary to do a good job of keeping the trees warm, usually wrapping the trunk with straw, plastic film, hay, etc., to protect the cold and keep warm, and prune the dead branches and leaves of the plant before winter, reduce nutrient consumption, and water the antifreeze water once after pruning, and apply a phosphorus and potassium fertilizer to improve the cold tolerance of the tree.

In the process of maintaining trees in winter, it is necessary to reduce the amount of water and fertilizer, do not apply frequently, affect the normal growth of the root system, and the trees for bonsai maintenance usually overwinter indoors, at this time, it is necessary to open windows regularly for ventilation and provide sufficient light to the plants.