Black cancer on an apple tree: treatment and photos

Studying the enemy

Black apple canker is a highly harmful fungal infection, which is popularly called “Anthony's fire” or “fireworm”. Many types of fruit trees are susceptible to this disease, but apple trees are most often affected.

Infection with black cancer occurs in the spring. Spores can overwinter in fallen leaves, rotten fruit, and even in the folds of healthy tree bark. When suitable weather conditions occur, awakened spores, falling into fresh damage on the tree, begin to grow in the intercellular space of tissues, causing the death of plant cells. After this, the fungi continue to develop as necrotrophs, feeding on the dead remains of the plant.

Is the disease dangerous?

The areas of the tree affected by cancer cannot be restored. However, at the initial stage, the spread of infection can be stopped. Tree cancer is only dangerous for the apple tree itself.

For wood

Apple tree canker can be caused by summer leaf fall. In this case, the tree will lose all its foliage long before the onset of cold weather. Having lost its leaf mass, the apple tree will not be able to accumulate nutrients for wintering. A tree can die from frost in winter.

Branches affected by cancer dry out, break and fall to the ground. Deep putrefactive cracks form in infected areas of the trunk, and the tree above the affected area dries out. The disease is dangerous for the apple tree. After all, because of cancer, a tree can die.

For man

Apple tree cancer is caused by fungi or bacteria that parasitize the tree. These microorganisms do not affect human health and do not penetrate the body. True, eating rotten fruits is not recommended. If the apples do not have rotten spots, they can be eaten.

Optimal conditions for infection

Warm, rainy weather in spring is favorable conditions for the germination of spores that cause apple tree cancer. April-May are potentially dangerous months for an orchard, since rising air temperatures, heavy rainfall and damp soil due to melting snow are a suitable environment for the development of any fungal infections.

Black cancer on an apple tree.

Positive temperature

Temperatures from +5 degrees and high humidity contribute to the awakening of spores. The higher the air temperature, the higher the rate of spread of the fungus in healthy tissues.

Poor quality trees

Typically, trees that become sick are old, exhausted, and also those injured during winter (frozen, damaged by rodents). In this case, the tree does not have enough strength to form immunity and quickly regenerate damaged tissue.

The stronger the bark, the less chance the fungus has to penetrate the tissue.

Incorrect care or lack thereof

Lack of preventive treatment of trees against fungal diseases also leads to infection with black cancer. In addition, the cause of the disease can be improper pruning, untreated areas of cuts and cuts. An open wound is a favorable condition for the penetration of pathogens.

Excessive grooming

Excessive care can also cause the spread of fungal infections in the garden. Excessive nutrient content in the soil favors the development of pathogenic microflora.

Incorrect landing

Factors that increase the risk of fungal infection that must be taken into account when planting:

excessive deepening of the root collar;
the distance between the trees and the compost pit is less than 3 m (actively decomposing organic matter can become a “shelter” for pathogenic microflora and a source of infection);
poorly drained area with stagnant water;
placing trees too close to each other leads to the rapid spread of the pathogen throughout the garden.

Preventive measures

Proper care will help avoid infection

Preventive measures are related to the basic rules of agricultural technology when growing garden crops:

The planting of trees is planned taking into account the recommended distance between them of 3 m or more, avoiding the proximity of compost pits with organic matter to them, while for planting preference is given to places that are closed from constant exposure to sunlight, because constant exposure to ultraviolet radiation often leads to foliage burns, which becomes a favorable factor for the development of fungus;
for proper air circulation, the apple tree crown is regularly trimmed, maintaining an angle of more than 45°;
they uproot old, obsolete apple trees, or if they intend to preserve them, they thoroughly clean the tree bark, which improves gas exchange and destroys possible fungal spores and pests that have accumulated under dead tissue;
whitewashing is carried out at a height of up to 2 m, incl. in the spring until the buds open and in the fall after the leaves fall;
In regions with unfavorable conditions for black cancer due to climatic conditions conducive to the occurrence of infection, varieties resistant to the fungus are planted.

Varieties resistant to black cancer

Gardeners in regions with warm and humid climates, when choosing varietal varieties of apple trees, opt for those resistant to canker fungus:

show average resistance Spartan, Orlik, Pinova, Redfree, etc.;
summer - Papirovka, Alva, Baagaevsky, etc.;
autumn - Borovinka, Freedom, Korichno, etc.;
winter varieties - Jonathan, Stoykoe, Lobo, Zarya Alatau, etc.

How to recognize

The initial stage of the disease may be asymptomatic and only after a week or even a month will signs of black cancer appear. Having discovered the first signs of black cancer on an apple tree, begin treatment immediately.

Bark

Damage to tree bark is especially dangerous. In this case, the tree dies completely within 3-4 years. The incubation period for bark infection is 15-27 days.

Black cancer on the trunk of an apple tree.

In early spring, you need to carefully examine the trunk and skeletal branches of trees. First of all, you need to make sure the integrity of the bark. If you find any fresh wounds on the wood, you need to examine each damage in detail. If infection has occurred, the wound will be surrounded by black dots (pycnidia) arranged in circles.

The fungus is growing rapidly. The active phase of the disease is characterized by the appearance of black spots with a purple or brown tint. Destructuring of the bark occurs, it peels off and crumbles. Damaged areas become charred. Eventually, the dead tissue encircles the skeletal branches and trunk of the tree.

Flowers

When apple tree flowers are infected with black cancer, the petals acquire a brown tint, become shriveled and dry out. The stamens and pistil turn black.

Fruit

Mostly mature fruits are susceptible to infection. When fruits are infected, the incubation period lasts 6-9 days. Then dark spots appear that grow throughout the fruit. The apple shrivels and mummifies. The color of the fruit is black without any shade or brown.

Leaves

On the foliage, the fireweed appears in the form of red-brown spots. After a while, the center of the spot turns gray and circles appear around it. Then the number of spots increases, the leaves begin to dry out and fall off. In 1.5-2 months, a diseased tree can completely lose its foliage.

Disguise

Black cancer successfully masquerades as other diseases. It can be confused with diseases that cause similar damage. Therefore, before you start fighting black cancer on an apple tree, carefully study all the symptoms of the disease that appear. If you remember the main differences between the manifestations of these diseases, you will be able to correctly diagnose the disease and begin its treatment:

cytosporosis leaves gray spots on the bark, which subsequently do not turn black (i.e., there is no charring effect);
With cytosporosis, the bark does not crumble, but takes on a worn-out appearance;
with ordinary cancer, swellings and tumors with dark red tubercles form on the cortex;
Moniliosis, like fireweed, colors the fruits black, but with a blue tint.

Black cancer often occurs simultaneously with other fungal infections.

Apple tree with traces of black cancer.

Types of diseases

There are several types of apple cancer. The infection affects those trees that have damaged bark, fresh cuts or wounds.

Black

Apple tree cancer develops when the fungus Sphaeropsis malorum gets into cracks in the bark or wounds. It reproduces by spores that are carried by the wind. Cancer most often affects the branches and trunk. Brown spots appear on the area affected by the cancer infection; after a while they darken and grow. The bark swells and falls. The infection can penetrate inside the trunk; it will no longer be possible to save such an apple tree.

The leaves of a tree with cancer become covered with red-brown spots with black dots inside. Dark spots appear on the apples, the fruits begin to rot and turn black, mummifying right on the branch.

Ordinary

The disease is caused by the fungus Nectria galligena. This cancer is called European cancer. The infection affects the trunks and branches of apple trees. Brown spots appear on the tree. Over time, the bark dies, and a growth (swell) or deep crack appears at the site of the wound.

Common cancer has 2 forms - open and closed. The infection penetrates into cracks and cuts. In the closed form, cancerous growths completely cover the wound, leaving only a gap filled with rotten mass. Most often, old or weakened trees are affected. When the form is open, deep, non-healing wounds are formed. At the site of the lesion, the wood rots.

Root

The causative agent of the disease is the bacterium Agrobacterium tumefaciens stevens. The disease is not so easy to notice because it develops underground. Numerous pea-shaped growths form on the roots. Bacteria penetrate into the roots through cracks. Over time, the tumors reach large sizes (10-12 centimeters). Apple trees affected by root canker grow quickly at first, and then their growth stops.

A tree infected with cancer does not bear fruit and develop well, because bacteria take away nutrients. The disease does not rise above the root system. The bacteria live for a long time in neutral or slightly alkaline soil, where apple trees have been planted for many years.

Bacterial

Bacteria infect flowers, fruits, branches and trunk of the apple tree. A characteristic sign of bacterial cancer is the leakage of an orange-colored sticky substance from a crack in the bark. Affected wood becomes dark, soft, and damp. Brown spots appear on the leaves, and less often on the fruits, but they remain hanging on the branches. Cancer infection is activated in rainy and warm weather.

How to cure an apple tree from black cancer

If a lesion with damage characteristic of the final stage of a cancer infection is located on a trunk or skeletal branch, the tree is removed. Because it is impossible to cure a dying apple tree from black cancer. In other cases, it is possible and even necessary to treat the tree.

Cleaning

Before you start treating apple tree cancer, you need to sanitize the trees and the area:

remove infected foliage and fruits;
cut down infected branches;
Apple trees with critical damage must be uprooted;
burn infected parts in a specially designated place.

Operations on apple tree trunk bark and skeletal branches

Skeletal branches, completely surrounded by cancerous tissues, are cut down entirely below the place bordering healthy tissues. Topical lesions on the branches or trunk are cut out, capturing some healthy tissue.

Cleaning the trunk of an apple tree from black cancer.

After the manipulations have been carried out, you can proceed directly to the treatment of black cancer in the apple tree.

Disinfection and isolation of the wound

All cuts obtained during wood sanitation must be immediately disinfected. A 1-3% solution of copper sulfate or a concentrated solution of potassium permanganate is suitable for this purpose. Then the wound is “sealed” with garden varnish or special oil paint to prevent the entry of air and moisture, which can trigger a relapse.

Apple tree processing

Since firefly is spread by spores, sanitizing the tree alone will not be enough. All parts of apple trees are susceptible to cancer infection, so the entire tree needs to be sprayed with fungicide.

Garden treatment

Since we have to fight apple tree cancer in a comprehensive manner, all fruit crops in the garden must be treated with fungicides. In addition, it is advisable to treat the soil in the tree trunks with antifungal drugs.

Folk remedies

Some believe that the use of “chemicals” harms not only the environment, but also the person himself. Therefore, there are always enthusiasts offering various folk remedies as an alternative to chemistry.

The following can be used as disinfectants:

iodine-saline solution;
a solution of ordinary 72% laundry soap;
ground sorrel leaves mush;
concentrated manganese solution.

With potassium permanganate you can not only disinfect saw cuts and cuts, but also wash the entire tree to wash off pathogenic spores from it.

A mixture of clay and mullein

Instead of garden varnish and other special means for treating wounds, you can use folk recipes.

Clay and cow dung are mixed in a 1:1 ratio, water is added to obtain a viscous consistency, convenient for spreading. The mixture should be of medium thickness so that it does not clump or spread.

The resulting mixture is applied in a very thick layer to cleaned, disinfected wounds, bandaged and again covered with a thick layer. Throughout the growing season, the coating is regularly moistened with water and additionally lubricated with fresh mixture.

A mixture of rosin, wax and nigrol

If nigrol is somehow preserved among the old supplies at the dacha, you can prepare a putty based on it. To do this, you need to heat nigrol, rosin and wax (paraffin) in a 1:1:1 ratio in separate containers. Pour rosin and wax into the hot negrol and mix thoroughly. The resulting putty can be stored in glass jars and used as needed.

This mixture is used as a regular garden varnish.

Treatment of apple trees for black cancer.

garden soil

Some gardeners use garden soil pre-treated with a fungicide as a putty. The soil is moistened and the disinfected wound is coated with it. After rains, the procedure is repeated.

Apple tree bark

Particularly advanced gardeners use the following method:

A piece of bark is cut from a healthy donor tree, the shape exactly suitable for closing the treated wound on the apple tree.
The bark is tightly applied to the wound, aligning all the edges, and bandaged.
All joints and cuts are carefully covered with garden varnish.

Additional treatments for black cancer

In the fight against black cancer and other fungal diseases of fruit crops, gardeners often use a very strong manganese solution. It has excellent antibacterial and antifungal properties.

To treat wood against fungal spores, potassium permanganate is diluted with water (5 g per 10 l) in a glass or plastic container. The resulting solution is used to treat not only wounds, but also the entire bark on the trunk and branches. In this case, you need to literally saturate the bark with the solution, washing away the spores. After washing the wood, spray the leaves and fruits.

Treatment of apple tree cancer with antibiotics

This method is used in industrial gardens in Europe, since it is believed that antibiotics are more environmentally friendly drugs than chemicals.

Antibiotics such as streptomycin and tetracycline are used for treatment. Treatment consists of sequentially spraying the garden with a solution. Spraying begins with streptomycin, and next year it is replaced by tetracycline.

Stem injections

Injection treatment does not require preliminary sanitary treatment of the diseased apple tree; you simply need to treat the tree with fungicides. Injections are made by introducing the antibiotic streptomycin into the wood of the trunk:

A hole is drilled in the bark of the apple tree a meter from the ground, through which the antibiotic is injected.
After administering the drug, the hole is sealed with a stopper.
Each skeletal branch thicker than 15 cm is taken as a separate trunk, into which an antibiotic is also injected.
The medication is administered weekly, up to five times in total.

Treatment of an apple tree for black cancer with stem injection.
Unfortunately, antibiotics only help get rid of bacterial types of diseases, which black cancer does not include. But this method will definitely help get rid of other diseases that often develop in parallel with black cancer.

Drugs for fighting

Drugs used in the treatment of black cancer of apple trees are conventionally divided into three groups:

for disinfection (antiseptic treatment of wounds with industrial preparations) – garden paste “RanNet”, biobalm “Robin Green”, garden anti-cancer putty “ZSP”;
for treatment against spores (preparations of contact and systemic action, used for spraying the crown and soil) - “Fitosporin”, “Chorus”, “Topaz”, etc.;
to improve immunity (“Baikal EM1”, “Zircon”, “Gumat P”, “Obereg”, “NV - 101”, etc.).

Copper-containing drugs

Preparations containing copper are used to disinfect wounds; they can also be sprayed on trees, because copper has a depressing effect on fungal spores. In addition, copper sulfate is used to enrich the soil with microelements.

Due to its versatility, copper sulfate is included in many popular gardening preparations for various purposes. The most popular are “Bordeaux mixture”, “HOM”, “Oxychom”, etc.

Feeding

To speed up the healing process, apple trees need to be fertilized with mineral fertilizers. Organics cannot be used in this case, because its presence in the soil can provoke a relapse of the disease.

Treatment with antifungal drugs for humans

You need to immediately understand that fungal diseases of plants and people have different etiologies, so medications for treating human fungus cannot affect plant fungus. There is no point in treating apple trees with human antifungal drugs and expecting a positive result.

Conclusion

Black apple cancer is a serious disease that requires immediate treatment. The effect of treatment will depend on the stage of the apple tree disease. Currently, there are many methods and drugs to combat this disease, but the best of them is the tree’s own immunity. Its protective forces, which are formed by following agricultural technology and simple rules for caring for an apple tree.

If it was not possible to save the garden, then it is advisable to remove all the plantings along with the roots, burn them and wait a couple of years when the earth is cleared of spores and all pathogens. Then it will be possible to grow new young seedlings.

Treatment time for black cancer

Operations should be planned for early spring or late autumn, when the sap flow process is as slow as possible:

In the spring, before mid-April, it is necessary to carry out sanitary pruning and treat the wounds of the apple tree. Afterwards, before the buds open, treat the trunk and crown with a fungicide. After flowering, the apple tree is subjected to repeated antifungal treatment.
In the autumn, after leaf fall, sanitary treatment is carried out by pruning fungus-affected branches and cleaning wounds. All sections are treated with an antiseptic and sealed. After sanitation, the trees are sprayed with fungicides, the trunk and skeletal branches are whitened.

Prevention

For prevention, it is necessary to follow several rules of agrotechnical measures:

timely pruning of trees to prevent thickening of the crown, timely treatment of cuts and wounds;
maintaining distance when planting apple trees to avoid the rapid spread of the disease if infection does occur;
mandatory balanced feeding - apple trees that are fertilized correctly and in a timely manner have good immunity to various types of diseases;
proper preparation of the garden for wintering: cleaning and removing debris from tree trunk circles, mandatory whitewashing of trunks and skeletal branches to protect against sunburn;
organizing drainage systems to prevent moisture from stagnating in the soil near the tree trunks.

Preventive treatment of apple trees against black cancer.

Resistant varieties

Preventive measures will protect the health of the plant

Gardeners advise using zoned varieties that are adapted to the local climate and have good resistance.

Currently, there are no crops that are absolutely resistant to this disease, but there are some subspecies that are least damaged by the infection:

Several varieties are less susceptible - Redfree, Banana, Antey, Alesya, Rubin, Orlik, Pikant and Pinova;
summer - Papirovka, Malt Bagaevsky and Alva;
autumn - Freedom, Borovinka, Autumn Joy, Cinnamon Striped;
winter ones - Bolotovskoye, Kharalson, Jonathan, Lobo, Memory of Pashkevich and Zarya Alatau.

Champion, Pink Anise, Antonovka, Renet Golden, Renet Simerenko, Sava, Wilhelm, Wanda, Memory Kovalenko, Raika and Slava Primorye have weak immunity.

Adviсe

Here's what experienced gardeners advise:

Diana: “It is easier to prevent any disease than to try to cure it later. Therefore, provide proper care to your apple trees and prune them in a timely manner with disinfected garden tools, so as not to transfer the infection from sick trees to healthy ones.”

Anatoly: “Black cancer is curable, I know from my own experience. The main thing is to detect the disease in time and begin treatment, and then take mandatory recovery measures.”