Contents
The bark on the trunk of a pear cracks for various reasons, often they are associated with temperature changes, winter frosts and sunburn. But sometimes a violation of the surface layer occurs due to improper care. The main methods of treatment and prevention are described in the article.
Why did the bark on a young pear crack and peel off
Cracking of the pear bark occurs for a variety of reasons. Even if a tree is well cared for, it can suffer from frost and temperature changes. Sunburn, disease and insect infestation are not ruled out. The main reasons are described in the following sections.
Frosts
Very often, the appearance of cracks is associated with adverse weather conditions in winter. These include not only severe frosts, but also temperature changes, as well as high humidity. If it periodically warms up, and then sharply cools, moisture is absorbed into the bark and solidifies, greatly increasing in volume. After that, the surface layer is strongly compressed, and the bark begins to crack. The resulting cracks are called frost cracks.
In winter, there may be several similar cycles associated with temperature changes. As a result, damaged areas become even larger. Therefore, if in the spring it turns out that a pear trunk or large branches have cracked, the reason is probably related to unfavorable weather.
Diseases
The bark can crack due to black cancer
Another reason why the bark on a pear cracks is associated with diseases. Most often this is due to black cancer (another name is Antonov fire). The disease is of fungal origin. It leads to an active loss of moisture by the tissues of the cambium and the cortex. As a result, the following symptoms appear:
- black, “charred” spots;
- drying of leaves;
- falling flowers and ovaries.
Due to cancer, pear bark can crack, development slows down, and yields drop dramatically. Usually pathogenic fungi penetrate through frost holes. Therefore, the infection often appears after an extreme, little snowy winter. In some cases, the disease spreads so quickly that even young, healthy pears die in just 3-4 months.
Another reason why the bark can crack is associated with cytosporosis. This is a fungal infection, which is manifested by drying and dying of branches. At the same time, they do not change color, which is why it is quite difficult to recognize the pathology in the early stages.
vermin
The bark of the pear also begins to crack due to the effects of pests. They can be conditionally divided into two groups:
- Insects that gnaw through small passages in the thickness of the bark. They also damage the bast and other tissues. This is a bark beetle, nutcracker and weevil. As a rule, it is difficult to notice them on the surface, since the pests go under the bark. You can determine the invasion by the presence of small holes (entrances and exits). The bark will crack, dry out, and the shoots will bend.
- Sucking insects – aphids and bedbugs. They feed on plant juices of young shoots and soft tissues. Because of this, the pear bark will also suffer – it will begin to dry out and crack.
Separately, one should consider such an insect as the bark beetle. This is a small black beetle, the body length of which reaches only 4 mm. Very dangerous, activated during flowering. It can fly long distances, it affects pears, apple trees and other crops. On a tree, females gnaw through passages under the bark and lay eggs, and it is almost impossible to notice pests.
From the eggs, larvae appear, which also make moves in the tissues of the wood. The following spring, they pupate, new beetles appear, and the cycle repeats. Due to gnawed moves, the pear bark will crack. This will negatively affect the yield.
If the flour is white, and deep-lying tissues are damaged, the tree may die.
The surface layer can crack due to weevils, aphids and other pests.
Sunburn
If the bark on a pear is cracked and flaking, this could be due to sunburn. Moreover, it is not the sun’s rays that are dangerous in themselves, but temperature changes. Usually in March, in the regions of the middle lane, the weather changes dramatically. During the day, the sun is already very warm, and at night the temperature drops, often to -10 degrees.
Cells are activated due to the effect of heat, but due to a sharp jump, they die. As a result, the bark will crack, deform. These processes are more active due to unmelted snow. Sunburns are especially dangerous for young trees that have not yet formed a sufficiently powerful bark. At the same time, burns often affect not a pear, but an apple tree, a sweet cherry, a peach and a plum.
Too much nitrogen fertilizer
If the bark cracks on a young pear, the cause may also be due to an excess of nitrogen compounds. Gardeners make such dressings for a quick set of green mass, and in general this is the right measure. But it is important to observe the dosage, since overfeeding is often more dangerous than underfeeding. If you regularly abuse nitrogen top dressing, many new shoots will appear, and in winter a significant part of them will freeze.
Another gross mistake is related to the timing of nitrogen fertilization. If you give them in the second half of summer or autumn, the tree will not be able to prepare for a dormant period. It will continue to grow, the branches will suffer from frost, and the bark will begin to crack.
Rodents
In winter and spring, pests also damage trees – primarily mice and hares. They feed on young bark, which causes water to accumulate in the holes. Then it freezes, increases in volume, which causes cracks to form. The situation is exacerbated by temperature fluctuations and the lack of sufficient snow.
What to do if cracks appear on the trunk of a pear
If cracks appear on the pear trunk, it is necessary to start treatment as soon as possible. The affected area is carefully cleaned with a sharp knife. The blade is pre-disinfected in a solution of potassium permanganate 1 g per 1 liter.
After that, the wound is left for several hours to dry and treated with one of the drugs:
- Bordeaux liquid 2%;
- iron vitriol 1%;
- fungicide (according to instructions);
- manganese 1 g per 1 l.
In the spring, after pruning, pears are treated with fungicides.
After thorough spraying, you must again wait for the surface to dry completely. Then they are processed with garden pitch. You can purchase it or make your own by mixing clay and mullein in a 1:1 ratio.
The last stage of treatment is to apply a tissue bandage to the affected area, where the pear bark began to crack. You can take any natural fabric as a basis, for example, cotton or burlap. It is tied with ropes or a special tape. Do not use wire – new wounds may occur.
Preventive measures
If the bark on a pear cracks, it is not always easy to treat a tree, and in some cases it is impossible to help it. Therefore, it is recommended to take preventive measures in order to prevent such problems. One of the important techniques is shelter, which is especially important for regions with frosty and little snowy winters. It is also recommended to whiten the trunks every year and feed them in a timely manner.
Whitewash
To prevent sunburn, it is recommended to whitewash the trunks and branches of the tree every spring with lime milk at a concentration of 20%. Both the trunk itself and the large skeletal branches of the first and second tiers are whitewashed. Copper sulphate and casein glue should be added to milk of lime to prevent diseases and protect against damage by frozen drops of moisture.
Shelter
To prevent the pear trunk from cracking, it is necessary to prepare the tree for winter
After pruning in the fall, all plant residues are carried away and burned. The trunk circle is mulched with peat, hay, sawdust and other materials (layer height of at least 10 cm).
But in regions with frosty winters, this is not enough. To prevent the bark from cracking from extreme temperatures, the trunk and large branches of the pear are tied with newsprint. You can also wrap it in spruce branches or reeds (in the south this is unnecessary).
Newsprint protects the tree well from adverse weather. It retains heat, prevents overheating of the trunk under the bright spring sun. It also protects against rain, as it gets wet first and dries out pretty quickly. Thanks to this, the pear bark will not crack.
Additional fertilizing
To prevent cracking, it is necessary to carefully observe the rate of application of nitrogen fertilizers. At the end of March or at the beginning of April, it is enough to give a pear 100 g of urea or 20 g of ammonium nitrate. Instead, you can use liquid organic matter, for example, an infusion of 500 g of litter per 10 liters of water.
So that the pear bark does not begin to crack, in the fall, after pruning, it is recommended to dust the near-stem circle with wood ash (about 200 g per square meter). Instead, you can give superphosphate and potassium sulfate (30 g each). These substances help to strengthen the root system and increase winter hardiness.
Conclusion
The bark on the trunk of a pear cracks mainly due to adverse weather and improper care. Also, the reason may be associated with the invasion of pests or fungal diseases. Therefore, for prevention, it is necessary to treat with fungicides every spring. In summer, the trees are periodically inspected and, if signs of insect invasion appear, they are sprayed with insecticides.
