The walnut has been grown by people since ancient times, not only for its valuable seeds for food and oil, but also for the wood used to make furniture, various items decor, gun butts.

It has been established that the walnut grows well and bears fruit in areas where the annual rainfall is not less than 500 mm and not less than 250 mm during the growing season, the relative humidity is 60-80%, ground water lie no closer than 1.5-2 m, the average annual temperature is +9 ... + 10 ° С, and the decrease in air temperature to extreme values ​​\u200b\u200b(-28 ... -30 ° С) and frosts during the period of blooming and flowering is a rare occurrence. In this regard, it is very difficult to get ripe walnut fruits in the northern regions.

Like any other crop, the walnut is damaged by diseases and pests from the first years of life. The most dangerous of them will be discussed below.

American white butterfly

It is a dangerous quarantine pest. It damages almost all fruit species, developing, in the conditions of the south, in 2 generations: in July-August and in August-September. However, in the case of a long warm autumn, the butterfly can give the 3rd generation. The 2nd generation does the most damage.

Young caterpillars damage the leaves and young shoots of the walnut, first in places of concentration of colonies, and then, spreading along the tree, they are able to destroy the entire leaf mass.

One of the ways to fight the butterfly is to remove and burn caterpillar nests, use trapping belts to collect and destroy pupae. Trapping belts are made 15-20 cm wide from corrugated paper or burlap.

On the garden plot it is highly undesirable to use insecticides (even those approved for use in household plots), therefore, if funds allow, it is better to purchase one of the modern microbiological preparations:

1. Bitoxibacillin (40-80 g / 10 l of water) - spraying should be carried out during the growing season against each generation of the butterfly with an interval of 7-8 days. During flowering, processing is prohibited. Consumption of working fluid - 2-5 l / tree (depending on the age and type of tree). This drug is registered in Russia by OOO PO Sibbiopharm until 2020.

2. Lepidocid (20-30 g / 10 l of water) - the application is similar to bitoxibacillin.

3. Dendrobacillin (30-50 g / 10 l of water)

Attention! Before using these drugs, you must carefully read the instructions (concentration and method of application may vary) and clarify whether it is allowed for use in household plots according to the “State Catalog of Pesticides and Agrochemicals Allowed for Use on the Territory Russian Federation» for the current year.

apple codling moth ( Cydia pomonella L)

Damages all fruit species, including walnuts. In the conditions of the south it develops in 2 generations: in May-June and August-September.

Caterpillars of the 1st generation appear in early June and damage young fruits (eat the nut kernel), which subsequently fall off.

The most harmful is the 2nd generation. The appearance of caterpillars falls on August. They penetrate into the nuts through the base of the fruit and eat out the cotyledons. Damaged fruits fall off prematurely. One caterpillar can damage several fruits.

To combat the apple codling moth, trapping belts and regular collection of carrion worms are used. It is possible to use insecticides permitted in household plots.

Nut Warty Mite ( Aceria erinoea, formerlyEriophyes tristriatus)

The size of an adult individual is not more than 0.1 mm. It hibernates in dormant buds on the plant and causes the main damage to the leaves until they are fully developed. Mostly young and middle-aged plants (under conditions of sufficient moisture) suffer. The mite rarely damages the fruit.

As a result of the vital activity of the mite, numerous dark brown galls resembling small rounded warts are formed on damaged leaves throughout the leaf blade.

To combat the tick, it is necessary to use acaricides approved for use in household plots.

Nut Miner Moth

The pest develops in 3 generations (in May, June and August), but 2 and 3 are the most harmful. Younger caterpillars bite into young leaves and feed on their pulp without damaging the skin. This kind of damage is called "mines". An adult caterpillar does not “mine” a leaf, but lives in a rolled leaf, eating it.

The fight against this pest should be given great attention, since in the case of uncontrolled reproduction, the mining moth can cause significant damage to walnut trees.

Control measures. Treatment with the microbiological preparation lepidocid, organophosphorus insecticides, with a high number - pyrethroids approved for use in household plots.

Brown spotting, or marsoniosis

The causative agent of the fungus Marssonina juglandis(Lib.) Magn. The disease affects leaves, green shoots and fruits. In early or mid-May, small round spots of brown or light brown (later grayish) color with a wide brown border are formed on young leaves. The spots often coalesce. Affected leaves fall off prematurely. Small depressed red-brown spots form on the ovaries. In places of damage, the tissue lags behind in growth, the fruits shrivel, crack and, often, prematurely crumble. Sometimes they rot, the core deteriorates (blackens, dries up) and becomes inedible.

In years with heavy rainfall in the first half of summer, especially favorable conditions are created for the development of brown spotting, which leads to large yield losses, sometimes up to 50% or more. The pathogen overwinters in fallen leaves and in affected shoots.

Control measures. Collection and burning of fallen leaves. Early spring (before bud break) treatment 3% Bordeaux mixture(300 g blue vitriol and 450 g of quicklime per 10 liters of water). To curb the development of the disease during the growing season, 2-3 treatments with 1% Bordeaux mixture or fungicides are carried out. In case of an outbreak of the disease, 1-2 treatments are carried out with an interval of 10-15 days.

bacteriosis

The causative agent is a bacterium Xanthomonas arboricola p.v. juglandis. The disease manifests itself in the form of dark spots on leaves, branches, fruits and inflorescences. Bacteriosis is especially to be expected if the weather is warm and damp in spring.

Insects, pollen, etc. can be carriers of bacteria. Pollen, falling on the stigma of pistillate flowers, accelerates the introduction of bacteria into them. During flowering, the disease can destroy up to 90% of flowers and young ovaries.

Infection at a later period leads to less severe consequences. Affected green shoots die off, the wood inside turns brown. On the fruits, the spots gradually increase and become brown. Later, the affected areas are pressed and blacken.

Bacteria can enter the nucleus of young fruits, causing rotting. Such fruits shrivel and fall prematurely. In ripened fruits, the nucleus is not damaged, but the pericarp is mainly affected.

The pathogen overwinters mainly in diseased shoots, leaves and buds.

Control measures. Treatment of walnut trees before flowering with a solution of 3% Bordeaux mixture or 1% urea. The second spraying is carried out 15-20 days after flowering with a solution of 1% Bordeaux mixture and 0.3-0.4% urea solution.

Root cancer, or goiter of the roots

The causative agent of the disease is rod-shaped bacteria Agrobacterium tumefaciens Smith & Townsend living in the soil. They penetrate the roots of plants through cracks and wounds. Under the influence of bacteria, the cells of the affected tissues begin to intensively divide, forming growths and swells on the roots and root neck.

With a strong infection, especially with a lack of moisture, plant growth stops. At good care for plants, the harmfulness of the disease is significantly reduced.

To prevent the disease, walnut seedlings should be planted in areas where long time did not grow fruit and berry crops, grapes, root crops and other plants affected by root cancer.

When planting, the seedlings are carefully examined, the growths found on the roots are removed. After pruning, the roots of seedlings should be disinfected for 5 minutes with a 1% solution of caustic soda (100 g per 10 liters of water), and then rinsed. Seedlings in which the main root or root collar is severely affected are burned.

1. Lugovskoy A.P., Murzinova D.G. Improvement of the walnut cultivation system in the North Caucasus. — UDC 634.5: 631.541

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Despite the fact that the walnut is resistant to various types of diseases and pests, the plant cannot fully resist them. Find out what diseases a walnut can get, what pests to be wary of, and how to help a tree in such cases.

So that the walnut does not get sick and is not damaged by pests, it is necessary to keep the main trunk, skeletal and perennial branches in order. Every year, you need to cut the shoots growing inside, affected by diseases, dried branches. Places of cuts should be covered with garden pitch or oil paint, and the fallen nuts to collect and burn.

If a autumn leaves walnut collect in a metal container, pour boiling water and close tightly, then by spring you will have a concentrate that can be used to prepare a remedy against aphids and the Colorado potato beetle.

What can cause walnut disease?

The main diseases of the walnut - Marsoniosis(bacterial spot) and bacteriosis.

Small light spots, turning black over time, on the leaves of young shoots indicate damage to the nut bacterial spotting. The disease begins with the defeat of the tops of young shoots. If you notice affected shoots, remove them immediately. In affected fruits, the kernel liquefies and acquires an unpleasant odor.

bacteriosis affects leaves, young shoots and fruits. The first signs of the disease appear on the leaves - first, black spots form on them, which gradually grow along the veins. Affected leaves are deformed, blacken and fall off. On young shoots appear elongated brown spots, subsequently the affected shoots dry out and bend. In wet years with insufficient heat and frequent fogs, the disease can kill up to 90% of the flowers. Young fruits affected by bacteriosis fall off.

How to protect a tree from diseases?

The main protection of the walnut against fungal diseases is the treatment of trees with copper-containing preparations. It is best to use ordinary Bordeaux liquid for this purpose. Its substitutes (Tsineb, Hometsin) are less effective and require more frequent spraying.

The first spraying with 3% Bordeaux liquid is carried out even before the buds open. Then switch to a less concentrated 1% solution and spray plants with it in the following development phases:

• in the phase of opening leaf buds;
• before the flowering of female flowers;
• immediately after flowering;
• at the very beginning of fruit formation.

Instead of Bordeaux liquid, before bud break, trees can be treated with a 1% DNOC solution.

Processing a walnut with Bordeaux liquid will be even more effective if you add a 0.3% solution of urea to it, which has a depressing effect on the causative agent of bacteriosis.

walnut pests

The main pests of walnuts are american butterfly(white), which is classified as a quarantine pest, codling moth, nut miner moth, walnut wart mite. Almost all types of pests can be fought with almost the same drugs, since most of them belong to gnawing and sucking species.

In their development, almost all pests go through the caterpillar stage, in which they hibernate on trees. Therefore, to combat them, it is imperative to use trapping belts. Getting on a tree, the pests form huge colonies covered with a dense web (American butterfly), fold the leaves into a tube (tick) or settle inside the leaf blade (mining moth), and then spread throughout the tree.

How to deal with pests?

The main control measure timely pruning and burning damaged branches. The main thing is not to let the caterpillars crawl along the tree.

Do not use pesticides, it is better to use one of the biological products against pests: Lepidocide, Bitoxibacillin, Dendrobacillin. Before use, be sure to read the instructions and follow the specified concentrations. The consumption of the working solution per 1 tree is at least 3-5 liters.

During flowering, walnuts cannot be treated with chemicals, because. they can kill bees and other pollinating insects.

At severe damage caterpillars, moths and mites during the period of fruit growth, you can spray the trees once with Decis Profi. The drug has a short decomposition period, so it does not accumulate in plants.

Although the walnut is resistant to different kind diseases and pests, the tree still needs some care. And if you follow the measures described above, then a healthy and beautiful tree will certainly please you with a good harvest.

walnut diseases

Walnut, like any other living organism, can get sick.

The main causes of walnut disease can be: improper care, infertile soil, lack of sun rays, excess moisture, nearby groundwater, harmful insects.

In this article, we will learn about the most common walnut diseases, the treatment of walnut diseases and find out which insects harm the walnut and how to deal with them. Let's start with walnut pests.

Walnut: pests

American white butterfly

Most dangerous insects for walnuts is the American white butterfly. The American white butterfly damages almost all fruit tree species. An insect can develop in two or three generations:

first generation - July-August

second - August-September

the third - September - October.

Caterpillars of the American white butterfly settle on the shoots and leaves of the walnut, and later spread throughout the tree, destroying all the leaves on the tree.

Fighting methods

Methods for controlling the American white butterfly include burning nests (along with caterpillars), using trapping belts to collect and further destroy caterpillars, or using microbiological preparations.

Nut codling moth

Nut (apple) codling moth also damages all fruit tree species. The codling moth develops in two generations:

first - May-June

second - August - September

The first generation of codling moth caterpillars damage the walnut kernel, subsequently the nuts fall off.

The second generation of caterpillars settles inside the walnut and eats the cotyledons.

One caterpillar can damage several nut fruits, the nuts fall prematurely, which negatively affects the yield.

Fighting methods

To combat the codling moth, pheromone traps are used. These traps contain a certain agent that attracts male codling moths, thereby reducing their numbers and the number of fertilized females.

Also, do not forget to regularly collect wormy carrion and inspect the walnut for the presence of caterpillars.

Nut warty mite

The walnut warty mite is a kind of "minor dirty trick". Its size does not reach even 1 mm. The nut mite damages the leaves before they develop, because.

it lives in dormant buds. Recognizing the "work" of the tick is quite simple: it leaves small but numerous dark brown "warts" on the leaves.

Acaricides are used to control ticks.

No less harm to the walnut is caused by aphids, sapwood and moth-moth. To combat these pests, special solutions, microbiological preparations and sanitary tree felling are used.

walnut diseases

If we talk about walnut diseases, then first of all comes to mind brown spot.

Walnut and brown spot

Brown spotting (Marsoniosis) affects walnut fruits, green shoots and leaves.

Brown spotting most often occurs during prolonged rains, when too much moisture accumulates in the soil.

This walnut disease is especially dangerous during the flowering period of the tree. During this period, it is able to destroy up to 90% of the flowers, which will undoubtedly have a negative impact on the crop. As for the affected fruits, they either shrink, crack, rot, or crumble.

Fighting methods

To combat brown spotting, walnuts (even before buds appear) are treated with 3% Bordeaux mixture. Fallen leaves are burned.

root cancer

Root cancer is a disease that affects root system tree. Cancer enters the roots of the tree through wounds and cracks. A sign of this disease are convex growths. because of severe defeat root cancer, the walnut may stop its growth and fruitfulness.

Fighting methods

Methods for dealing with root cancer include removing growths on the roots, treating the roots with a 1% solution of caustic soda, followed by washing the roots of the tree with running water.

Bacterial burn

Bacterial burn is especially dangerous disease walnut. This disease affects the leaves, shoots, flowers and fruits of the tree.

Watery spots can be seen on the leaves and petioles, which later turn black, but the leaves do not fall off for a long time. Ulcers appear on the stems. Shoots wither, buds die.

Black spots also appear on the fruits, the walnut kernel turns black and dries up. Liquid droplets appear on the affected areas.

The disease will spread faster in the rainy season. Carriers of fire blight are insects and pollen.

Fighting methods

To combat this disease, copper-containing drugs are used. Severely affected walnut trees are culled, the fruits are destroyed.

So, we looked at the most common walnut diseases, learned what walnut pests exist and how to deal with them. Regular inspection of a tree is the best prevention of any disease.

Tatyana Kuzmenko, member of the editorial board of the Sobcorrespondent of the Internet publication “AtmAgro. Agroindustrial Bulletin”

(37 , average:

Source: http://atmagro.ru/2015/02/16/greckij-orex-bolezni-i-ix-lechenie/

walnut diseases

Walnuts are often used for decoration. landscape design and making a profit.

This species produces many fruits, so many grow it for the purpose of selling it. It happens that walnut diseases occur.

To deal with them, it is necessary to determine the causes of their appearance, one of them is improper care.

White butterfly - one of the walnut pests

Causes

Gardeners are wondering why walnut diseases appeared. Wrong care is the main provocateur of disease.

Main factors:

• long spring frosts;
• hail or acid rain;
• rainy weather;
• depleted soil.

Not all factors depend on the actions of the gardener, it is impossible to influence the weather, but there are ways to help the tree. Treatment after long rains by special means, and in frosty spring, the nut should be covered with a film.

Brown spots on wood

If black spots with a brown tint appear on green walnuts, then this indicates a fungal disease (marsonia). The cause is excess moisture.

The disease immediately affects young shoots and only then passes to adults. Brown spots appear on the leaves, which eventually cover it completely.

If marsonia appears during the flowering period, it will destroy all the flowers and no fruit will appear.

To cope with such a disease, it is necessary to use Bordeaux liquid. With its help, you need to process the tree three times. This tool can be prepared independently, you need quicklime and copper sulfate in equal parts.

You can use preparations that are sold in gardening stores. The most popular are Strobi and Vectra. These funds can be used as a preventive measure.

Brown spots indicate a fungal disease

The danger of bacteriosis for walnuts

Bacteriosis is a walnut disease, due to which a black spot appears on the tree, the leaves fall off.

The disease negatively affects not only the plant itself, but also its fruits. With bacteriosis, the fruit ovaries fall off along with the leaves.

If the nuts remain on the tree, then the result is fruits of not very high quality.

Bacteriosis can develop in any part of the tree. It occurs due to an excess of moisture or a large amount nitrogen fertilizers in the soil.

To fight the disease you need to be patient. All fallen leaves are immediately collected and burned. The tree should be treated with copper sulphate. If the disease has severely affected the nut, then it is better to use Bordeaux liquid for this. Treatment is carried out in two or three stages.

Bacteriosis is manifested by characteristic dark spots

root cancer

Root cancer is the most dangerous disease of the walnut. It enters through various cracks in the tree.

You can detect the affected areas by the bulges that appear on the trunk and root. If a nut is ill with this disease, then it will stop growing and bearing fruit.

At the last stage of cancer, the tree dies.

The fight against the disease is to remove growths from the roots. If this is not done, it will be impossible to save the tree. After removing the growths, the places of their formation are treated with a solution of caustic soda, washed with water.

Root cancer can completely destroy a tree

Pests as the cause of disease

Walnut pests are as dangerous to him as diseases. Sometimes their appearance is the cause of the disease. One of the walnut pests is the codling moth. Because of it, the nuts begin to crumble ahead of time.

To prevent its occurrence, it is necessary to regularly remove the nests that the caterpillars create from the tree.

A large number of white butterfly causes the leaves to fall off. If you do not fight it, then the tree will lose its green foliage ahead of time.

The pest actively attacks the walnut from July to September.

If you see caterpillars or pupae on a tree, they should be immediately removed and burned. You can get rid of the butterfly only with the help of special preparations ("Dendrobacillin" and "Betoxibacillin").

Source: http://SeloMoe.ru/oreh/bolezni-greckogo.html

walnut diseases

Walnut is one of the most common types of fruit trees, known since ancient times for its nutritional and healing qualities.

Mostly walnut plantations are in private farms.

It is difficult to imagine a peasant economy, country cottage area or a front garden without overgrown walnut trees.

Walnut belongs to long-lived plants, specimens are known that grow and bear fruit for 400-500 years. This tree leads its history from Turkey, Central Asia and northern India.

Today, the zone of growing walnuts has expanded significantly and the “royal acorn”, namely the ancient Romans called these fruits, organically fit into the garden culture of many peoples.

Walnut fruits are rich in trace elements and vitamins, especially vitamins E and C, carotene and tannins. Walnuts are added to the diet for diseases of the heart, blood vessels, anemia and many other ailments.

Regardless of the place where the walnut grows - private sector or collective farming - these trees, like all living organisms, are subject to many diseases. The walnut is affected by about fifty diseases, the most common of which are: brown and white spotting, phyllosticosis, ascochitosis and many others.

Of course, an indispensable and most important event in the cultivation of walnuts is competent and regular phytosanitary protection of plantings, which largely determines the productivity of trees.

The result of these activities directly depends on the correct combination of agrotechnical, biological and chemical methods protection, regularity and methodical work to protect the garden.

When choosing one or another method of protection, the feasibility and type of pesticides used, a study is necessarily carried out to determine the source of infection, the number of pests and the affected area.

The most dangerous and common diseases of walnut trees include bacteriosis, spotting, late blight, damage by mites and codling moths, and a number of others.

bacteriosis

Bacteriosis is the most famous and, unfortunately, the most widespread disease of walnuts. Today, scientists do not know varieties of these trees that are resistant to this infection.

Bacteriosis affects all ground parts of the tree, buds, leaves, flowers, young branches and green (milk) nuts suffer from it. The foliage of an infected tree is covered with large black spots, the leaves seem to shrivel, turn black and soon fly around.

On young sprouts, oblong brown spots also appear and the sprouts, like the leaves, turn black, twist and dry. It has been established that the disease spreads through infected flower stalks (earrings) of the walnut.

A sick tree drops its ovary. With a later infection with bacteriosis, the quality of the nut kernels decreases. The causative agents of the disease hibernate in the middle and on the bark of the nut, and in the spring they enter other organs of the nut through the buds and cracks in the branches and trunk.

The disease develops especially transiently in rainy weather, leading to a total infection of the tree.

Among the methods of prevention and control of walnut bacteriosis, agrotechnical measures are the most common.

These include the collection and burning of affected leaves and twigs, as well as methods chemical processing trees.

The latter include wood treatment with copper sulfate, copper oxide, Bordeaux liquid.

brown spotting

With a disease of brown spotting (anthracnose) of a walnut, the foliage and directly the fruits of the tree are affected.

This disease is very common and affects not only nuts, but also tomatoes, strawberries, plums and cherry trees. When infected with brown spot, rounded spots appear in a multitude on the foliage of a tree.

It typically occurs in mid-summer and is accelerated by wet and rainy conditions.

Spots first appear on sprouts and young branches, then ulcers form, and over time, the sprout bends and dies, or subsequently takes on irregular shape. In disease-damaged fruits, the skin of the skin of the nucleoli darkens, and the nuts themselves acquire a rancid taste.

They fight brown spotting by collecting and burning fallen infected leaves, as well as regular (twice a month) spraying with a one percent solution of Bordeaux mixture.

The greatest harm to walnut trees, which leads to a decrease in tree productivity, a deterioration in the quality of nuts and, ultimately, to diseases and death of trees, includes walnut moth, aphids, and codling moth mites.

nut moth

The walnut moth brings the greatest harm even in the nursery, infecting young seedlings of nuts. Mature trees also suffer from this pest, in which the nut moth destroys the leaves.

Young caterpillars of the nut moth gnaw out the juicy middle of the leaves, leaving the dense upper layer foliage.

To combat the walnut moth, trees are sprayed with pesticides, which are used when spraying many other types of fruit trees.

Aphid

Aphids also primarily attack nut seedlings. The source of nutrition for aphids is the juice of leaves and buds, eating them, the aphid thereby weakens the entire plant. Pesticides fight against aphids, in particular, a decis solution is often used.

codling moth

The codling moth is recognized as one of the most dangerous pests affecting walnut plantings.

If the fruit tree is damaged by the codling moth, then soon the fruits fall from it, and later, with the continuation of the disease, the codling moth caterpillars infect the kernels of the nuts, penetrating into the shell through the stalks.

In this case, the nuts remain on the tree, but they completely lose their commercial qualities. To destroy the codling moth, the disposal and burning of fallen nuts, as well as spraying trees with insecticides, are used.

Nut warty mite

The walnut mite is an extremely small pest, its size does not reach even one millimeter. This pest settles in the buds and infects the leaves even before they bloom.

As a result of its vital activity, the tick leaves behind tiny multiple brown-brown, wart-like growths on the leaves.

Pesticides are also used against ticks, a wide range of which is presented in specialized stores.

Source: http://ogorodnikam.com/derevya/bolezni-greckogo-orekha/

Walnut pests than to spray a walnut against pests - Proposition

Ukraine is one of the largest walnut producers and exporters. According to the Center for Industrial Growing, the annual walnut harvest in the country is 75-85 thousand tons (according to some sources, up to 100 thousand tons).

), about two-thirds of this amount is exported to other countries. The current needs of the population of Ukraine in nuts are satisfied only by 40%. One of the priorities is the environmental friendliness of cultivation.

It is believed that nuts can be grown as an organic crop, that is, without the use of protection products and fertilizers. But the realities of life dictate their conditions.

Right now in different countries more than 100 walnut pests have been registered in the world.

Walnut is one of the most unpretentious plants in terms of soil conditions and agricultural technology. It is grown on carbonate soils, constantly loosening and fertilizing the surface.

Young trees suffer from frost, so they need to be spudded for the winter. At proper care nuts grow quite quickly, giving 1-1.5 m of growth per year.

Walnut trees mercilessly exploit the soil: the groundwater level under them drops sharply, the soil turns to stone, even grasses cannot withstand such a neighborhood.

Walnut leaves contain poisonous substance- juglandin. Rains wash it out of fallen leaves into the soil and inhibit the development of other plants.

In the south of Ukraine, in the region of potential industrial cultivation, walnut leaves, branches, fruits and stems damage and infect about 50 types of diseases and pests of the walnut.

One of the most common walnut pests in all areas of cultivation - walnut gall, or warty, mite(Eriophyes tristriatus Nal., Family Eriophyidae).

It hibernates in the buds, causing the main damage to young leaves before they are fully developed.

By damaging the leaves, it causes the formation of humpbacked thick-walled bulges (galls) on their upper side due to the introduction of salivary enzymes during feeding.

On the underside of the leaf, depressions are formed, densely covered with hairs, the so-called ereniums, in which ticks live. Several (up to four) generations develop during the growing season. Rarely damages fruit. From late August to mid-September (depending on the region), this walnut pest migrates under the scales of the kidneys, where it winters.

Nut gall mite- a pest that damages only walnut plantations. Distributed in the right-bank regions of the Forest-Steppe and Steppe, in Podolia. A low number is still observed in Polissya and in Central Ukraine.

Feeding on the leaves, mites cause deep pathological changes. Young and medieval trees suffer the most: leaves fall prematurely, their general oppression is observed, productivity decreases in subsequent years, and the decorative effect of trees deteriorates.

Some experts believe that the nut gall mite is a carrier of bacterial diseases, including bacterial nut spot.

It is quite difficult to deal with this walnut pest, because in places of damage it forms galls - large rounded swellings, the leaves from below are covered with thick yellowish felt.

In this felt covering (ereniumi), mites are well protected - even most acaricidal preparations do not have a pronounced systemic effect. Optimal timing struggle - May - early June, that is, the period when migration and reproduction of ticks in galls occurs.

Apple codling(Laspeyresia pomonella L., series Lepidoptera (Luskokrili), family Tortricidae (Leaf rollers)) is a polyphagous pest.

It is distributed everywhere in Ukraine, damages apple, pear, quince, apricot, plum, hawthorn, chestnut, and the form L. putaminana Strg - walnut fruits.

In the conditions of the south of Ukraine, the pest develops in two generations: the first - in May - June, and the second - in July - September. Caterpillars of the first generation appear in early June and damage young fruits, causing them to fall off. One caterpillar can spoil up to 10 fruits.

Butterfly codling moth dark gray with dark transverse stripes and a large oval yellow-brown spot, with a golden-copper sheen on the top of the wing, wingspan - 18-20, body length - about 10 mm.

Butterflies fly in May - June, in the evening twilight and at night, and during the day they sit motionless on the branches and trunk, merging in color with the bark.

At night air temperatures above 15 ° C, butterflies begin to lay eggs, placing them one at a time. smooth surface leaves or fruits. One female is able to lay from 40 to 220 eggs.

The eggs are round, flat, whitish-transparent, 0.9-1.3 mm in diameter. The embryonic development of the egg, depending on the temperature, lasts up to 10 days. The revived caterpillars are whitish-pink, about 2 mm long, with a dark head.

As they feed, which lasts up to 38 days, and grow, the caterpillars acquire an intense pink color. At the end of feeding, they pupate in places where branches branch, under the bark, at the root collar, under clods of earth, in weeds.

Butterflies of the second generation appear in July, caterpillars are reborn within eight to ten days from the beginning of the summer of butterflies.

The most harmful walnut pests are the second generation caterpillars, which are reborn during August. Penetrating inside the walnut through the base of the fruit, they eat out its core.

Some of the damaged fruits may fall prematurely, and those that remain on the trees lose their marketability. The walnut pest overwinters in the pupal phase in the web of a cocoon under the bark and in the soil.

To protect crops from codling moth it is necessary to constantly carry out phytosanitary monitoring of the walnut pest using pheromone traps. Since butterflies fly high, traps should be placed at the top of the canopy.

In small plantations, traps are hung out at the rate of 1 pc / 100 m2, on large arrays - 1 pc / 2 ha. Traps are checked every three days.

When catching more than five butterflies a week, it is recommended to treat with pesticides after 7-14 days (they are used during the rebirth of caterpillars, while they have not yet managed to get into the fruit). If the number of butterflies caught in a trap is less than the threshold of harmfulness, the use of pesticides is inappropriate.

One of the ways to regulate the number of apple codling moth in small gardens walnut - mass capture of males on pheromone traps.

To catch butterflies, you need to use one trap for one mature tree or two or three young ones. As the adhesive tab in the trap fills, it is either cleaned or replaced.

It should be borne in mind that positive results can be expected by conducting mass capture of butterflies for several years in a row.

In any case, the use of pheromone traps will ensure the destruction of some males and thereby significantly weaken the pest population.

With some settling of plantations by the codling moth, food traps (fermented sweet solutions of syrups, jams, kvass) and fishing belts are used, as well as mandatory collection and destruction of carrion. By the beginning of the summer of butterflies (around April), you should carefully examine the bark of trees, its crevices, especially in the lower part of the trunk, and destroy wintering cocoons with pupae.

How to spray a walnut from pests

Chemical protection of walnut plantations from the pest is very problematic.

This is due to the fact that walnut fruits contain oils in which organophosphorus and some other insecticides can dissolve and abstain.

Alternatively, trees are protected with avermectin-based biopreparations produced by Streptomices avermitilis, Pseudomonas aureofaciens and Bacillus thuringiensis.

Unfortunately, there are no pesticides allowed to protect walnut plantations from harmful organisms.

Therefore, business executives should make a lot of efforts to prevent pests from settling walnuts, while using the agrotechnical and mechanical protection measures given above.

For the destruction of pests that are massively divorced in plantations, we recommend using chemicals, in particular from the groups lambda-cyhalothrin, thiamethoxam, thiacloprids, chloranthraniliproles, allowed for protection fruit crops. Despite the fact that the norms and methods of processing these drugs may differ depending on the manufacturer, you should be guided by the relevant instructions.

In 2015 on walnut trees The American white butterfly (Hyphantria cunea Dr., order Lepidoptera, Ursa family (Arctidae)), which belongs to the objects of internal quarantine, developed quite actively.

The American white butterfly (ABM) is a polyphagous pest that damages (according to various sources) 250-300 plant species. Most often this fruit trees, walnut, elderberry, hops, grapes.

The pest develops in two generations.

Under natural conditions, they withstand frosts down to -30 ° C, but are very sensitive to sudden temperature changes in the spring.

Butterflies fly out at the end of April - the first decade of May, lead a twilight lifestyle. At this stage, the pest is snow-white, with a wingspan of 25-35 mm, in some specimens even up to 40-50 mm, body length is 9-15 mm.

caterpillars younger age are greenish-yellow in color, with age they become brownish with black warts on the back and orange on the sides. The thoracic shield and ventral legs are black.

In 2015, the American white butterfly (Hyphantria cunea Dr., Lepidoptera series, Ursa family (Arctidae)), which belongs to the objects of internal quarantine, developed rather actively on walnut trees.

American white butterfly (ABM) is a polyphagous pest that damages (according to various sources) 250-300 plant species. Most often - these are fruit trees, walnuts, elderberries, hops, grapes.

The high harmfulness of ABM lies in the ability of caterpillars to completely eat leaves on plants, which they wrap in cobwebs, forming nests.

Due to damage to the leaf surface, the photosynthetic activity of plants decreases, metabolic processes are disturbed, which, in turn, affects the yield, winter hardiness, protective functions and often leads to the death of plantings.

This walnut pest develops in two generations.

Pupae hibernate under the lagged bark of trees, in the branching of branches and crevices, plant remains, and other protected places.

Under natural conditions, they withstand frosts down to -30 ° C, but are very sensitive to sudden temperature changes in the spring.

Butterflies fly out at the end of April - the first decade of May, lead a twilight lifestyle. At this stage, the walnut pest is snow-white, with a wingspan of 25-35 mm, in some specimens even up to 40-50 mm, body length is 9-15 mm.

Feeds on nectar flowering plants and does no harm. Females lay eggs in groups of 200-350, mostly on the underside of leaves. One female can lay up to 1500 eggs.

The laid eggs are spherical, smooth, bluish or yellowish, 0.5-0.6 mm in diameter. The revival of the caterpillars occurs after 14-25 days.

Young caterpillars are greenish-yellow in color, with age they become brownish with black warts on the back and orange on the sides. The thoracic shield and ventral legs are black.

After feeding, the caterpillars pupate. The pupa is lemon-yellow, becoming dark brown with time, 8-15 mm long, located in a loose, dirty gray cocoon. The pupal stage lasts up to 20 days.

In July, butterflies of the second generation appear, which are highly prolific - the female lays up to 2500 eggs.

Having finished feeding, the caterpillars of this generation pupate in September - October and hibernate at this stage.

Plantation protection system - quarantine, agrotechnical, chemical and biological measures aimed at limiting the number of pests and preventing its spread throughout the country.

Quarantine measures include: the introduction of quarantine in areas where the pest is found; constant surveys of plantings and its destruction in the centers of detection.

Agrotechnical measures include: - rarefaction of the crown and removal, cutting and destruction of branches with caterpillar nests;

Cultivation of row spacing for weed control;

Plant nutrition.

Chemical and biological control measures for the American white butterfly, if necessary, are applied against each generation of the pest during the development of younger caterpillars.

As a rule, chemical treatment is used to destroy the first generation of caterpillars.

Means of protection against caterpillars of the second generation are selected depending on the intensity of development and abundance of the pest, according to the "List of pesticides and agrochemicals permitted for use in Ukraine".

To prevent the spread of the pest in walnut plantations, it is necessary to carry out high-quality protective measures on other neighboring fruit crops.

Since the agrobiocenosis of walnut plantations always has a certain supply of harmful organisms - pathogens and pests, in order to control their numbers and preserve trees, phytosanitary monitoring and a combination of various methods protection - agrotechnical, biological and chemical.

M. Konstantinova, cand. s.-x. Sciences, consultant

Information for citation

Dangerous walnut pests in the South of Ukraine / M. Konstantinova // Proposition. - 2017. - No. 2. - S. 156-158

Walnut is one of the most valuable fruits that nature has given us. It is widely used in various areas of our life. The walnut tree grows in almost every garden and about it healing properties already written in previous articles on this site. Making us happy every year abundant harvests walnut still has problems. Let's talk about the diseases affecting this valuable tree.

If dark spots appear on young leaves and green fruits of the nut and grow, thereby deforming them and leading to the fall of leaves and fruits. Your nut has spotted or anthracnose. This disease is caused by fungi that develop on the affected leaves of the plant.

External signs of the manifestation of the disease are the appearance of round reddish-brown or grayish-brown spots with a grayish center. And at the same time, rounded in-depth necrotic cracks appear on the pericarp.

If this disease appeared at the beginning of the season, then it can cause significant damage to the crop, as the nuts are deformed and fall off, and you can be completely left without a crop. And it must also be taken into account that at the end of the growing season, the troubles of the nut do not go away, since the fungus remains for the winter on unfallen fruits and leaves, various cracks and wounds of the branches. Fallen leaves also store danger, where the fungus is stored in the marsupial stage.

When spring comes, ascospores are carried by air currents to young shoots and again infect the walnut tree with the disease. The greatest infection occurs in wet weather, when rains and fogs occur during the flowering period of the walnut. Eat late flowering varieties nuts, here they are less exposed to anthracnose.

To protect the walnut from the disease, as a rule, spraying with Bordeaux liquid or preparations containing copper is carried out.

The first treatment is carried out before the leaves bloom at the beginning of the growth of earrings, the second - when the leaves reach normal size, and the third two weeks after the second treatment.

Another more common disease in nuts somewhat similar to anthracnose is bacteriosis or bacterial burn (black spot). In this case, young leaves and earrings are first affected. As soon as the bacteria reach the earrings, they infect the pollen grains, and the wind and insects do their job - spread the infected pollen.

Walnut can become infected at any time of the year, but a rainy spring is most conducive to this disease. Fruits are also affected by this disease. First, a small black spot appears on the tip of the fruit, and then it increases and covers the entire fruit. Infected nuts usually fall off the tree, but may remain on the branches. The diseased seed in the fetus turns black and shrinks, and the pericarp also turns black completely or partially.

Leaves affected by bacteriosis have a typical dark brown color and yellowish green edges.

To have healthy nuts, choose later-flowering varieties for planting and treat with Bordeaux liquid - take 8 parts of copper sulfate and 16 parts of lime for 100 parts of water.

Spray trees with this composition when earrings appear and pollen has not yet spilled out, the second - when the ovaries grow to 6 cm. In order not to damage the pistillate flowers with such a concentration of the solution, it must be reduced (100: 2: 4).

Another walnut pesters the warty tick. It settles on leaflets, and they become corrugated and develop poorly, and there can be 300 - 500 galls on one leaf. During the growing season, the tick inside the gall gives 3-4 generations and in mid-September leaves for wintering under the scales of the kidneys or uneven bark. And from the beginning of the growing season, it moves to young fruits and leaves, and causes the formation of galls.

For any living organism, the risk of disease is a natural process. Walnut trees were no exception. There are several reasons due to which the disease may occur - this may be the lack of proper care and poor soil with low fertility, as well as groundwater lying nearby, lack of sunlight, and even harmful insects. This article will describe the main diseases of the walnut and the fight against them.

This type of disease affects not only leaves and shoots (green), but also fruits. It is quite simple to determine this ailment - you will notice rounded brown spots on the leaves even with the naked eye. Leaves affected by spots fall off much faster. Most often, this disease manifests itself after prolonged rains, which is associated with the accumulation excess moisture in the soil.

Such a disease will be most dangerous for flowering nuts. In the worst case, spots will affect almost all flowers, and this, as you understand, will cause a low level of fruiting. If we talk about fruits affected by brown spots, then there are only two options - they will either crumble or dry out, after which cracks form on them and rotting begins.

Walnut diseases often lead to the death of the entire tree, so you need to deal with them in a timely manner. In order to get rid of brown spotting, it is necessary to treat the walnut tree with a 3% beard mixture before the buds appear. All affected fallen leaves must be burned.

root cancer

If we consider all diseases of the walnut, then root cancer is the most dangerous of them. As the name implies, cancer affects the root system of the nut. It penetrates into it through cracks and wounds that could have formed during the transplantation of the seedling. Of the signs of this disease - growths of a convex shape on the roots of the nut. If the roots are severely affected by cancer, the fruiting and growth of the tree can completely stop.

To rid the nut of this disease, you will need to completely remove all the growths formed from its roots, then treat the roots with caustic soda (1 percent solution), and then rinse them in running water.

Bacterial burns

This disease for a walnut is also extremely dangerous. Burns affect the flowers, fruits, leaves and shoots of the walnut. With such an ailment, if you carefully examine the petioles or leaves of the nut, you will notice spots of a watery kind, which later become black. It is also worth noting that the leaves with this ailment do not fall for a long time. Next stage- the manifestation of ulcers on the stems. The buds begin to die off little by little, the shoots wither. Black spots also appear on the fruits themselves, which leads to blackening and drying of the kernels. You may notice a few drops of liquid on the areas affected by such burns.

At the same time, constant rains during such a period will only help to progress bacterial burns. The disease spreads through insects and pollen.

To overcome this painful process for the nut, you will not be able to do without preparations containing copper. At the same time, severely damaged trees cannot be saved, so they have to be rejected. The nuts themselves in such a situation must be completely burned.

bacteriosis

If you decide to look at a photo of walnut diseases, pay attention to the symptoms of this disease. Most often it affects trees in spring time when kept relatively damp, but at the same time warm weather. With bacteriosis, you will notice dark spots formed on inflorescences, branches, fruits and leaves. If such a nuisance takes you by surprise during the flowering period of the nut, then most of the ovaries (young) and flowers will die. If the onset of bacteriosis fell on the period after flowering, then the green shoots will begin to die off a little, and the wood will turn brown. Walnut fruits are affected by dark spots that will grow rapidly every day.

AT winter period causative agents of bacteriosis hide in leaves, shoots (affected) and buds. To prevent such an ailment, it is necessary to treat the beard nut with a 3 percent liquid and urea (1 percent) before flowering. Subsequently, it will be necessary to spray again, but after flowering, not earlier than fourteen days later.

Walnut diseases: Video