How to spray an apple tree from scab in the spring and how to choose the processing time?

Scab is a common disease in apple and pear trees. It affects leaves, fruits, reduces yields, worsens the condition of trees and their winter hardiness. Therefore, gardeners, seeing the first signs of the disease on fruit trees, strive to spray the apple tree from scab as soon as possible. In advanced cases, when the tree has been sick for a long time, you cannot do without chemicals. If the spores of the fungus have affected only a small part of the crown, you can use folk recipes and process them with natural remedies.

How do you recognize a scab?

The disease is caused by spores of a marsupial fungus known as Venturia unequal. With the onset of spring, immediately after the first rain, the mushroom, having successfully overwintered in fallen leaves, sprays the infection around the garden. Pathogenic microflora spreads instantly, because up to 3 million spores can be thrown out of one bag at the same time.

It is difficult for an inexperienced gardener to detect the first signs of infection, which at the initial stage manifests itself in the form of light spots on leaves and young twigs. After a few days, the spots acquire a brown color, a velvety surface, blur, connecting with each other. At this stage, it is impossible not to notice that the apple tree is infected with scab.

The leaves turn black, dry up and fall off. Small brownish spots appear on the fruits, which increase in size with the growth of the apple. The pulp under the stain becomes hard, the skin of the fruit cracks, the apple begins to rot.

You can recognize the infection of an apple tree with scab by the following signs:

• light spots have appeared on the young leaves, which in the process of growth change color to brown, the surface of the spot becomes velvety;
• the fruits are covered with dark tubercles;
• tubercles stand out on the bark of the tree, which crack over time and release a new batch of spores.

The unequal venturia gets along well with other fungi, therefore, together with the scab, the apple tree can get several diseases at once.

Why is scab dangerous for fruit trees?

Most often, scab affects old trees with dense, neglected crowns. In order for the spores of the fungus to be thrown out of the bag, the leaf must be soaked through and through. Therefore, a warm rainy summer is the most favorable time for the development of the marsupial pathogen. Despite the fact that the fungus greatly weakens the tree, an apple tree affected by scab can live for a very long time. But it is unlikely that it will be possible to get a good harvest from a diseased tree.

Scab is dangerous for the garden for the following reasons:

• infected leaves dry up and die off, photosynthesis processes slow down;
• infected shoots will not produce high-quality fruits next year;
• if the buds and fruit ovaries are affected by the fungus, there will be no harvest;
• apples lose their presentation - they are lopsided, covered with black spots;
• fruits are poorly stored.

To protect your garden from infection with the marsupial fungus and to harvest a full harvest of fragrant and healthy apples every season, it is necessary to carry out preventive work and spray trees with special preparations in time.

How to get rid of scab?

The first measures to combat fungal disease are carried out in the spring, when a constant air temperature of more than + 10 ° C is established. During this period of rapid growth of green mass and the rapid development of shoots, you can treat the tree from scab with preparations containing copper.Bordeaux liquid or other chemicals of a similar effect must be thoroughly sprayed on the buds, trunk, ground around the fruit tree.

To increase immunity to fungal diseases, together with fungicide treatment, you can feed the apple tree with mineral fertilizers.

It is advisable to delay the beginning of the spring growing season a little. Then the scab spores, having awakened much earlier than the appearance of foliage, will not be able to develop so quickly. To do this, the plant is sprayed with salt water, dissolving 1 kg of table salt in 10 liters of liquid.

If, when examining young leaves, traces of scab are found, spraying with milk whey can be carried out before flowering. This product contains lactic acid bacteria that have a detrimental effect on fungal spores.

During flowering and fruiting, it is better not to use chemicals to fight scab, but to choose natural natural remedies. If, nevertheless, it was necessary to use chemical preparations, the last treatment should be carried out no later than one month before harvesting.

There are several effective means that will prevent massive infection of trees with unequal venturia spores.

Bordeaux liquid

Bordeaux liquid is the most popular drug that can be used to treat apple trees for scab. This copper-containing product is commercially available in powder or ready-to-use liquid form. You can make your own spray mixture by mixing solutions of copper sulfate and quicklime.

The first treatment is carried out before the onset of kidney awakening. At this time, use 3% Bordeaux liquid. With further treatments - and they can be carried out up to 6-7 times per season - use a 1% mixture.

This chemical only works where the liquid has been spilled. Therefore, spraying must be done very carefully, trying not to miss a single branch.

The drug lasts for about a month, and the chemical is not washed off by rain. However, do not overdo it with Bordeaux fluid. Excess copper can cause summer leaf shedding, resulting in the tree not producing fruit and preparing for winter.

"Hom"

The modern drug "Hom" is a worthy substitute for Bordeaux liquid. The composition contains chloride copper oxide. Produced in powder form, it acts exclusively on fungal spores without affecting plant tissue. To obtain a spray mixture, 40 g of the chemical is diluted in a little water, then poured into a 10 liter bucket, mixed and treated with infected trees.

"Oxyhom"

Due to the addition of oxadixil, Oxyhom not only successfully fights against the fungus, but also provides long-term systemic protection of the plant throughout the season.

"Raek"

Fungicide "Raek" is a modern systemic drug based on difenoconazole. Immediately penetrating all parts of the plant, the product protects it from scab damage for a whole month. During the season 3-4 treatments are carried out with the "Raek" preparation.

Biological fungicides

Compared to chemicals, microbiological agents have a more gentle effect on fruit trees. You can process apple trees with Alirin-B, Gamair, Fitosporin, whose work is based on the activity of various strains of hay bacillus. These preparations are safe for humans and allow processing not only during the period of bud extension and flowering, but also during the formation of fruits.

Folk remedies against scab on apple trees

Some gardeners fundamentally refuse to use chemicals and try to cope with fungal disease with folk remedies. The effectiveness of such a fight is usually no more than 50%. Spraying with herbal infusions will bring success only at the initial stage of garden infection.In cases where the disease is neglected and more than half of the fruit trees are affected by the fungus, only chemicals and bacteriological fungicides will help.

The following recipes are popular among folk remedies:

• spraying with a weak solution of potassium permanganate (5 g of powder per bucket of water);
• horsetail infusion - freshly harvested leaves of a plant are chopped into small pieces, poured with a bucket of water and infused for 3 days;
• mustard infusion - 100 g of mustard powder is diluted in 10 liters of warm water.

Experienced gardeners sometimes destroy spore clusters by burning tree trunks and branches with a gas burner. This is a very effective way, only to work with fire you need to have some experience. Otherwise, you can easily destroy the trees.

How can you prevent scab?

In order to prevent the appearance of scab in the apple orchard, it is necessary to carry out measures to prevent this fungal disease. For a young garden, it is better to choose a place on a hill where rainwater does not stagnate. It is important to carry out pruning in a timely manner, cut out dry forests and diseased branches, and plant varieties resistant to scab.

In autumn, fallen leaves must be removed from under the apple tree, and the soil must be dug up. After all, it is here that spores of the marsupial mushroom winter. If a lawn grows around the tree, then the soil can be sprayed with a 10% solution of ammonium nitrate.

An apple tree affected by scab can and should be treated. To do this, there are many chemical and bactericidal drugs that will help to cope with fungal disease. The main thing is to follow the instructions and continue processing until the scab completely disappears.