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If the bark of an apple tree is cracked, this cannot be ignored. The causes of such damage vary, but as a result the tree can weaken and even die. If affected by certain diseases and pests, there is a risk of the problem spreading to other plantings.
Types of cracks on the trunk of an apple tree
There are different types of cracks on apple trees. Their difference is not only in appearance and the nature of the damage, but also in the danger to the tree.
Ring
The damage extends between the annual layers of wood. Such cracks are also called peeling cracks.
The most dangerous is ring cracking of the bark of an apple tree, when the damage is encircling and closed. All tissues above the wound are left without nutrition, and therefore, without timely measures, they quickly die. The solution in this case must be radical. Bridge grafting is effective.
Transverse and longitudinal
Transverse damage is also called compression crack.It usually appears in young trees due to swaying by the wind or pressure from snow. Sometimes the apple tree cracks to the core.
A simple version of longitudinal damage is frost damage. If it is old, but looks like a roller. An internal crack may be closed or open.
Round holes
Typically, holes of this shape are small in diameter - only a few millimeters. This sign indicates pest damage. They penetrate inside the apple tree, disrupting its nutrition and development. As a result, the bark cracks and dries out. The problem is successfully resolved at an early stage.
Why does the bark on apple trees crack?
The bark on an apple tree cracks for various reasons. This may be due to weather conditions, or a sign of disease or pest infestation.
Cancer
When the bark of an apple tree bursts, the cause may lie in cancer - ordinary (European) or black. Both diseases are caused by dangerous fungi. The infection enters the apple tree through open wounds and damage.
With black cancer, red-brown spots first appear on the bark, then darken
Black cancer causes swelling of the bark and blistering. Gradually it peels off and falls off. The lesions turn black over time - hence the name of the disease. Not only the bark suffers, but also the fruits.
Black canker usually affects apple trees over 20 years old. Without timely treatment, the tree will die.
Common apple canker has similar symptoms, but it develops more slowly. It all starts with small dark brown spots. They look slightly compressed.Gradually the disease progresses:
- the formation of dark red tubercles – fungal spores;
- death of the bark and peeling off in round plates;
- the formation of deep wounds, with extensive swelling at the edges.
Cytosporosis
This fungal infection is dangerous for many fruit trees. As the disease progresses, the following signs appear:
- convex brown or black dots – the arrangement is chaotic;
- loosening the bark;
- drying out of branches, sometimes of the entire apple tree.
If the apple tree is severely affected by cytosporosis, it must be uprooted and burned to protect the rest of the plantings.
Frostbites or sunburn
It is not uncommon for the trunk of an apple tree to crack due to sudden cooling. This phenomenon is called frost damage. Its direction is usually parallel to the wood grain. A frost crack can be open or closed and often has swellings or ridges.
Sunburn usually appears in March. The reason lies again in the temperature difference - it gets sharply cold at night, and during the day the sun heats up the crust. The problem is made worse by the reflective properties of snow. The affected bark darkens, then peels and cracks. The damaged area falls off over time, exposing the wood.
The solution to both problems is common - you need to clean, disinfect and seal the cracks in the apple tree.
Frost damage to apple trees is typical for central and northern regions, where temperature changes are sharper and occur more often
Bacterial burn
This infectious disease of apple trees is typical for the southern regions; it appeared in Russia recently. General signs of damage are:
- wilting and death of inflorescences;
- curling and drying of foliage and stalks;
- the appearance of necrotic weeping ulcers on the bark;
- exudate on shoots.
When the bark of an apple tree cracks due to a bacterial burn, a sticky mass is released. At first it is whitish, then darkens. The dead cambium is exposed and turns red. Part of the crown or the entire tree may die within 12-14 months.
With a bacterial burn, not only the bark, but also the leaves, inflorescences, and fruits are affected.
Warming up
If the bark of a young apple tree or seedling is cracked, then the reason may lie in the undergrowth. The area near the root collar or slightly above it suffers. If the bark gets too hot, the apple tree may die. There are several possible reasons for the problem:
- dampness and temperature changes in late autumn and winter, when fabrics did not have time to ripen before the cold;
- unstable rootstock;
- snow cover is too deep.
When overheated, nutrition is disrupted, the apple tree dries out - stripping and putty are needed to solve the problem
Pests
If damage to the apple tree bark is represented by small round holes, then the cause usually lies in pest infestation. There is a whole subfamily of bark beetles, among which there are 140 European species alone. The size of the insect usually does not exceed 1-9 mm.
Wood dust can be found around the hole made by the bark beetle. With a deep cut, passages are visible inside the trunk. In addition to beetles, they contain larvae or clutches of eggs.
When attacked by a bark beetle, the branches dry out, the bark comes off in layers, and the apple tree may die
What to do if the bark on an apple tree bursts
When the bark of an apple tree cracks, it cannot be ignored. The solution to the problem must be comprehensive.
Treatment of wounds
If the trunk of an apple tree is cracked lengthwise or crosswise, but not in a continuous ring, then the damage can be healed. The process begins by cleaning the wound. The main stages are:
- Remove damaged bark.
- Cut out dead wood - it is darker than healthy areas.
- When stripping, capture healthy tissue.
After this, disinfection is necessary. It is effective to use iron or copper sulfate. Prepare a strong solution by adding 30 g of the selected drug to 1 liter of water.
Not only the cleaned wound on the tree is disinfected, but also the tool used. It needs to be processed both before and after. If there are several areas to be cleaned, then the tool is disinfected after working with each of them.
Putty
After cleaning and disinfecting, the cracks in the apple tree are treated so that the wound can heal. There are several options:
- garden var;
- clay mash;
- paint based on natural drying oil, mineral oils in the composition are unacceptable.
It is optimal to cover cleaned and disinfected wounds in the spring, before sap flow begins. The crack is treated when it dries after previous manipulations. As healing progresses, the putty layer is renewed as necessary.
If a frost hole is discovered only in the summer, then it can be roughly covered up. The damage will be thoroughly repaired next year.
If large saw cuts crack in summer or fall, it is important to prevent the damage from getting worse during winter. This will happen when moisture trapped inside freezes. To prevent the apple tree from cracking even more, the damage is filled with chalk, mixed with natural drying oil. Major cleaning and treatment is carried out next spring.
When an apple tree is cracked in half, in addition to treating the wound, you need to try to tighten the trunk. This is done using wire, not forgetting to protect the tree with rubber or felt pads. After pulling, the trunk is already treated with garden varnish. It is effective to mix fresh cow manure with fatty clay 1:2 and add copper sulfate (up to 1% of the total mass).
Graft
Typically, grafting to treat an apple tree is done when it cracks all over. The method is also effective for frostbites and sunburn. For grafting, you can use cuttings or root shoots. Branches growing below the damage are also suitable.
Bridge grafting is done when sap flow begins.
When the bark of an apple tree cracks, bridge grafting for treatment is done as follows:
- Prepare cuttings 10-12 cm longer than the damaged area. Any thickness is acceptable; if the affected area is small, the optimal diameter is 0.5 cm.
- Break off the buds from the blanks.
- Cut the cuttings diagonally on both sides.
- Clean the affected area and wipe with a damp cloth. All dead tissue must be removed.
- Trim the edges of the bark.
- Make T-shaped cuts above and below the exposed bark. Retreat 10 mm from the edge.
- Carefully bend the opposite edges of the cuts and insert the cuttings.
- Press the sections tightly against the wood and secure with a cloth soaked in garden varnish. It is more effective to use a composition with rosin.
- Arrange all the cuttings evenly and secure with a common wide bandage.
- Treat the bare area of the trunk with garden varnish to protect it from moisture.
The number of cuttings is selected according to the area of damage. They are harvested at the end of autumn or in December-January. When fixing cuttings, it is important not to confuse their top with bottom.
After grafting, the apple tree needs special care. It is regularly watered and fed with a potassium-phosphorus complex. If the apple tree is still young, a garter is required.
Sanitary pruning
When skeletal branches have a dead base, ring pruning is necessary. If the tissue remains alive, the fork is preserved. The damaged area is removed, and the growth bud is transferred to a lateral branch. It must be viable.
In some cases, only radical cutting helps. They resort to it when the trunk or branches crack extensively, and they cannot be saved in any other way. The affected parts are cut down in the spring or until mid-summer. The tree will recover when young shoots grow.
If pruning is done incorrectly, a hollow may appear over time; it must be cleaned and sealed.
Disease and pest control
The effectiveness of pest control depends on the timeliness of their detection. The following drugs are used against bark beetles:
- Inta-C-M;
- Alatar;
- Spark Double effect;
- Lightning Extra;
- Shar Pei.
A strong solution is prepared based on the drug. It is introduced into the holes made by the pest. For this you need a syringe with a long needle. Afterwards, the hole is immediately sealed using garden varnish. Effective recipe:
- Mix paraffin with rosin and vegetable oil 3:1.5:1.
- Boil the mixture for ten minutes.
- Cool.
Due to the danger of spreading, apple tree cytosporosis must be treated immediately. All cracked areas are cleaned, covering healthy tissue 2 cm in all directions. Tools are always disinfected during use.The sections are treated with copper (3%) or iron (5%) sulfate, then with putty. Fungicides are also used for healthy trees for preventive purposes.
To treat black cancer, cracked areas are cleaned, disinfected and covered with garden varnish. The healthy part of the trunk is treated with copper sulfate. After flowering, the leaves can be sprayed with Bordeaux mixture. Potassium permanganate is usually used for disinfection.
Fitolavin is effective for bacterial burns. The apple tree is processed five times after stripping.
What to do if the bark of a young tree is cracked
If the cause lies in illness, then standard measures for a particular case are taken. When there are small cracks on an apple tree, you can treat it like this:
- Carefully clean the affected area.
- Treat with garden varnish.
An alternative is transparent film. Cover the cleared area with it until it is overgrown. In young apple trees, the healing process is faster.
Prevention of cracks
When the apple tree is strong and receives proper care, it rarely cracks. To prevent such problems, a whole range of measures is needed:
- Choose the right planting location - a sunny area, remote groundwater, no flooding in the spring.
- Proper planting of an apple tree.
- Regular inspection of the garden.
- Autumn whitewashing of the trunk and skeletal branches. Treatment can be repeated in early spring. An alternative is to wrap the trunk with white paper.
- Regular sanitary pruning of apple trees.
- Treat wounds promptly.
- Apply fertilizers wisely - more nitrogen in the spring, potassium-phosphorus complexes at the end of summer and autumn.
- Carry out moisture-recharging irrigation to increase winter hardiness. An adult apple tree requires 200 liters of water, and a young one – 50 liters.
- Buy only healthy planting material.
- Preventive treatment against diseases and pests. Fungicides help against fungal infections. Alatar, Inta-Ts-M, Lepidocid, Bitoxibacillin are effective against pests.
An important point when planting an apple tree is maintaining the depth level.
To prevent the apple tree from cracking, furrowing is effective. It is made in late spring or early summer. The northern part of the trunk is cut lengthwise in 3-4 places from the base to the crown. If the apple tree is thin, one furrow is enough.
Conclusion
If the bark of an apple tree is cracked, it is important to identify the cause and begin treatment in a timely manner. Any problem can be solved if action is taken at an early stage. It's easiest when young apple trees crack. They recover faster and easier.
