Chestnut disease and how to treat them
 Chestnut disease

Chestnut is a very beautiful and powerful tree, which also brings useful fruit. One of the main problems of its cultivation are various diseases. and pests. Let's see why already in summer chestnut leaves rust and how to deal with it.

Chestnut Disease Control

One of the most important rules of tree care is its protection against diseases and pests. In no case should you skip preventive procedures., because to prevent the disease is much easier than to treat.

 Chestnut leaf curl
Chestnut leaf curl

But if the tree is still sick, treatment should begin immediately to avoid complications. Besides, some diseases and pests can lead to death or wilt chestnut.

Leaf spot: why leaves turn brown in summer

Diseases that appear on the foliage of the tree can be found quite often. Recently, regardless of the chestnut variety (regular, horse and others), the leaves begin to turn yellow in the middle of summer, and then become completely rusty. Usually, treatment started on time gives good results.

Perforated spotting Initially, small punctures appear on the leaves of the chestnut, which gradually develop into large brown spots, if you do not immediately begin treating the tree, then in a week the disease spread throughout the crown. When the form of perforated spot is running, ulcers and swelling are formed on the bark. There are many methods by which you can get rid of spotting, they are very easy to use and are available to every gardener.:

  1. First, you need to find out the cause of the disease and eliminate it. For example, make dressing chestnut, stop abundant watering or build around the tree a small shelter of pegs and film. These actions will help stop the spread of the disease;
  2. Every 10 days before the beginning of flowering and 1 time after it, the tree crown is treated with a weak solution of Bordeaux mixture, you can also use its substitutes, such as Azofos, Skor or Bayleton;
  3. The next method is more complicated, during the blooming of buds and after flowering the tree is sprayed with Bordeaux liquid, if the disease has spread, then such procedures will have to be repeated once a month throughout the season. For the best consolidation of the effect in preparing the tree for the winter, the crown is treated with 5% urea solution (5 grams per 1 liter of water), and the soil around it with 7% solution (7 grams per 1 liter of water).
Black spot Experts identify 2 reasons why such a disease occurs:

  • excessive moisture caused by too frequent irrigation or heavy rainfall;
  • lack of potassium in the ground.

If a black spot is formed on a tree, the leaves begin to turn black and fall off, there is also a general weakening of chestnut, slow growth and a decrease in the number of flowers.

Red brown spot At too high temperatures, dark red spots may form on the leaves, which gradually grow, begin to turn brown and cover most of the leaf. The disease may occur due to an excess of moisture or a sharp temperature drop (it is hot in the daytime, it is cold at night).
Brown spot Brown spotting differs from red-brown only by the tint of the spots and by the fact that they appear on both sides of the leaf.
In order to get rid of spotting once and for all, first of all it is necessary to remove and burn all the affected foliage, dig up the tree trunk and carry out sanitary pruning.

Mealy dew

The appearance of fungus parasites on plants can cause powdery mildew. Provocative factors are very different.:

  • hot weather, sudden changes in temperature and humidity have a positive effect on the multiplication of fungal spores;
  • also cause excess nitrogen fertilizer or lack of potash and phosphate dressings.
 Chestnut leaves are affected by powdery mildew
Chestnut leaves are affected by powdery mildew

Mealy dew covers the surface of the leaf and looks like a gray-white bloom, which is mycelium. Also characterized by the presence of dark brown balls (mushroom spores). Over time, the plaque becomes only thicker and, as a result, the leaf turns brown and falls.

Mealy dew spreads by air, infection is also possible through water or by direct contact of two trees. Therefore, it is very important to protect healthy plants from infection.

The fight against powdery mildew should begin with the removal of the affected leaves and their burning. It is also necessary to timely feed the chestnut with phosphate and potash fertilizers. Then the tree is treated with the following means.:

  1. Fungicides Bayleton, Topaz, But, Topsin, Fundazol, Skor, etc .;
  2. Biofugnicides Fitosporin-m, Gamair, Planriz, etc .;
  3. It is also effective tool, prepared from 500 grams of ash, filled with a liter of water. The mixture is infused for 2 days, then add 5 grams of laundry soap diluted in water and carry out the treatment, the procedure is repeated in a week;
  4. Experienced gardeners recommend spraying chestnut infusion of weeds and water, which is prepared in a ratio of 1k2.
All treatments should be carried out only in the evening to avoid sunburn.

Necrosis

Necrosis occurs when a tree gets burned, which may be caused by both the scorching rays of the sun and severe frosts. Also caused by mechanical damage.

Stem necrosis It can appear both on the branches and on the trunk of the tree, while the bark begins to crack and over time, cancer wounds and small seals appear (2-3 millimeters in diameter), the color of which can vary from pale pink to dark brown. It is worth remembering that for an adult plant necrosis is not terrible, and after several procedures, the disease disappears. But a young chestnut can die from such a disease.

For the fastest possible recovery, it is necessary to clean the damaged area with a sharp garden knife, treat it with a disinfectant and cover the wound with garden pitch. You can also spray chestnut Bordeaux liquid or fungicides.

Phomopsis necrosis Such necrosis is dangerous because it is very difficult to recognize in the initial stages. The course of the disease begins with the fact that harmful fungi settle under the bark, then the bark cracks and under it you can see a lot of small black bumps.
Septic necrosis The color of the bark becomes gray-white, and in its splits one can see black tubercles that indicate the presence of a harmful fungus.

 

 Regional necrosis of chestnut leaves
Regional necrosis of chestnut leaves

To avoid necrosis on chestnut you need to follow one simple rule, namely to whiten a tree in early spring and late autumn. Such a tool will protect the bark from both frost and heat.

Rot

Another problem of chestnut trees is rot, which affects various parts of the plant.

Root rot The disease is dangerous because if time does not take measures to treat the tree, then it can shrink and die. The cause of rotting of the root system can be soil pollution, high rainfall and the proximity of groundwater. In addition to the roots, such rot can climb a tree trunk (to a height of no more than 2 meters). If there is rot on the trunk or roots of a tree,it is already impossible to get rid of it. Damaged chestnuts are cut down, uprooted stumps and completely burn all the wood.

As a preventive measure, it is necessary to lime the soil and process it with fungicides (Bayleton, copper sulphate, etc.).

White stem rot White bloom with black stripes appears on the trunk of the tree, the height of the spread of the disease is 3 meters from the beginning of the root system. Most often, aging trees suffer from white rot.
Yellow Stem Rot The lower part of the trunk acquires a yellow, sometimes swampy shade, characterized by the presence of plaque.
Brown Stem Rot Usually found on stumps. The bark becomes dense, painted in brown, there are cracks.

 

Rot greatly weakens the tree, it becomes sluggish and stunted and can no longer fully cope with severe climatic conditions such as wind, frost, heat, etc.

Pests, what to do and how to fight?

Chestnut is often attacked by various pests, scientists account for more than 30 species of such insects, and some of them are extremely rare.

Pests are usually divided into the following groups.:

  1. Root - the May beetle is considered to be the brightest representative, whose larvae breed in the root system, and adult insects feed on foliage;
  2. Sucking - pests of this group feed on the sap of leaves, flowers and young shoots. Such insects include thrips, scale insects, aphids, and powdery worms;
  3. Leaf miners - One of the most common and dangerous pests that multiply very quickly and go to healthy trees. Chestnut moth larvae feed on foliage;
  4. Pests gnawing foliage - the elm leaf beetle and elm beetle feed on the leaf pulp, leaving holes in it;
  5. Stem - such pests can be met extremely rarely, their larvae feed on the core of the tree trunk, and adult individuals gnaw through the bark. These insects include bark beetles, mustaches, etc.

Mining Moth

Moth miner is the most dangerous chestnut pest. The main problem is that these insects are not fully studied, and experts have not derived the formula of the drug,which gives 100 percent results. The adult chestnut aphid is a butterfly 4 millimeters with folded wings. The insect larvae carry a threat; they settle in the foliage, gradually eating it. Such actions lead to early fall of the leaves.

 Larva of chestnut mining moth
Larva of chestnut mining moth

Treatment should begin with the removal and disposal of damaged leaves and branches of the tree, it is also worth remembering that larvae withstand temperatures up to -25 degreestherefore, it is necessary to process the chestnut for at least 2 seasons.

To get rid of insects use the following drugs:

  1. Special injections, for example, Karbusudfan or Imidloroprid. Injections should be made with a special pistol over the entire diameter of the tree trunk so that the drug is distributed evenly. Such drugs are quite expensive, but they are highly effective;
Such injections are a danger to human health, it is not recommended to make injections in populated areas, and in no case should the fruits of a “poisoned” tree be used as food.
  1. You can also spray chestnut hormonal drug Insegar.

Disease prevention than treating wood

If chestnut leaves turn yellow and dry - this is the first sign of tree disease. To prevent the occurrence of diseases and pests, you must perform the following steps:

  1. Regularly inspect chestnut in order to detect all changes in time;
  2. Carefully care for young trees, and feed regularlyand;
  3. Sanitary pruning of the crown and burn all damaged leaves and branches;
  4. Formed wounds need to be treated and lubricate with garden pitch;
  5. In the presence of chronic diseases during the vegetative period chestnut is treated with fungicides (drugs are selected in accordance with the diseases);
  6. Also preparations should be treated with mulchwhich is left under the tree so that the insect larvae could not spend the winter there.

In order to maintain a healthy and strong chestnut, it is necessary to carry out preventive treatments in a timely manner and to treat diseases and pests.