Most diseases of fruit trees are similar to the symptoms of pest attacks. Not all of them are easy to identify with the naked eye - the pear borer or the psyllid, a very small insect. But, even with a small size, these parasites multiply rapidly and simply destroy the tree. Before you start treating the plant, you need to highlight treatment methods and remedies; it is recommended to look at descriptions with photos of similar lesions. This problem can be dealt with in different ways - both chemical and less dangerous compounds.
Description
The pear psyllid or honey psyllid, as it is also called, is a small, winged insect with well-developed wings. It quickly jumps from one plant to another. The pest multiplies very quickly. The bodies of adult insects in the imago state are colored red-orange in summer. In winter their color changes to black. There are light stripes running along the chest in the longitudinal direction. The insect has transparent wings covered with dark veins. In a calm state, the copperhead folds them along the body. The size of adult insects reaches 3 mm.
The head of the copperhead is triangular with 2 large and 3 small eyes. The mouthparts of the psyllid are of the sucking type and are equipped with a proboscis. With its help, the insect sucks the juice from the leaves of the fruit tree. You can take a closer look at the insect in the photo below.
Biology
Honeydews are common almost everywhere where there are objects of their food: apple or pear trees. There are especially many of them in places with high air humidity, in particular in the North-West region of the Russian Federation, but other areas of the country are also not protected from the invasion of these dangerous pests.
Description
Medyanitsa belong to the psyllid family of the order Homoptera insects. They are very small in size and require some effort to see them. Judge for yourself, an adult insect barely reaches a length of three millimeters, and the larvae are even smaller - from a third of a millimeter.
The apple honeydew is greenish-yellow in color; by autumn the insects often darken slightly and acquire reddish tints.
The pest Pear Sorrel is colored a little differently. Her outfit is dominated by red and brown motifs. Moreover, just like its apple tree friend, the color darkens in the fall.
Lifestyle
Both the pear and apple honeydew are capable of both flying thanks to their transparent wings and jumping. In this she is helped by her hind limbs, developed like the legs of a grasshopper.
A little etymology! The jumping of psyllids on leaves, similar to those of fleas, gave the name to the psyllid family. And the insects received the name “sweetheart” for the sticky sweet secretions they leave on the branches and leaves of plants.
Adult insects also feed on quarantine trees, but they can also eat nectar from the flowers of other plants. The sticky secretions of honeydews attract ants and other insects that are not averse to eating the sweet stuff.
Development cycle
The parasite spends the cold season under the bark of trees or in fallen leaves. With the onset of spring and an increase in temperature to -2°C, it comes out. In regions with a warm climate, for example, in the Krasnodar Territory, Crimea or the Caucasus, the psyllid season begins in late February. In the central zone, where the weather is cooler, insects appear in the first half of March.
After the air warms up to +5°C, sexually mature individuals begin to reproduce. Egg laying begins when the temperature exceeds +10°C. Female psyllids that survive the winter live from 1 to 1.5 months. During this time, each lays several eggs. First, chains of eggs are found in the buds and under the bark of trees. The females then select blooming foliage and flowers for laying. The laying proceeds in several stages with a break of 5-7 days. During the summer season, up to 5 generations of the insect develop.
The rate of development of egg clutches depends on the ambient temperature. If the air is heated to +10°C, the eggs of the honeydew on a pear tree take 23 days to develop. When warming reaches +20°C, the entire process takes 7 days. The hatched nymphs move to the opening buds and young leaves and feed on plant sap. They then attack the petioles, pedicels and young shoots.
The entire development time from egg laying to the appearance of a sexually mature insect takes from 2.5 weeks to 2 months. The speed of insect development depends on the ambient temperature. Before turning into an adult, the nymph of the common pear honey molts 5 times:
- First instar nymphs are up to 0.54 mm long with an orange body and brown spots on the back. They have three-segmented antennae with one rhinarium.
- Second instar larvae grow to 0.72 mm. The body color changes to lighter.
- The body length of third instar nymphs increases to 1 mm. The hue changes to grayish-yellow, and a second rhinarium appears on the antennae.
- At the fourth stage of development, the larva grows to 1.35 mm. Its color changes to greenish-yellow. The size of the antennae increases to 5 segments. 1 rhinarius appears on the third segment and 2 on the fifth. Large wing cases appear, sometimes intersecting.
- Fifth instar nymphs have a body size of 1.9 mm. The shade changes to greenish-brown. The size of the antennae increases to 7 segments with 2 rhinarii on the seventh and one each on the fifth and third.
On a note!
The rate of development of larvae is largely determined by the quality of nutrition. Pests living on young shoots and foliage develop faster. If the tree's growth is disrupted, the copperheads die.
Nutrition and harm to fruit crops
Pests are sucking insects. Having left the eggs, they crawl along the branch for some time and, having pierced the bark with their proboscis, drink the juice. Then, having drilled through the swollen bud, they feed on young leaves. After blooming, the leaves are attached to the cuttings or stalks.
Affected trees become sick. The foliage falls off and turns yellow prematurely, and the ovary is lost. The leaves look underdeveloped - their area decreases. On branches covered with sweet secretions of flea beetles, colonies of fungi develop. In winter, damaged branches freeze slightly, and in summer, at the height of the heat, they dry out. The fruits on such trees are irregular in shape and partially woody.
Pests of indoor flowers bring a lot of trouble to gardeners, so it is very important to carry out preventive measures in a timely manner. Are you tormented by flies, are they constantly annoying with their buzzing and are you tired of catching them out of the jam? Then learn everything about anti-fly remedies from this article.
The barn weevil does not disdain anything - it likes any grain. You can find out how to get rid of this pest by following the link.
Lifestyle
Pear honeydews live in colonies. The main activity of parasites occurs in the evening and at night. They prefer hot and dry weather. If it's cloudy or cool outside, psyllids look for warm shelter. Eggs and larvae that do not have time to turn into adults die with the onset of cold weather.
Colonies of psyllids are often surrounded by foraging ants. These insects exist in symbiosis, like with leafhoppers or aphids. Ants help honeydews to overwinter, and they, in turn, provide food. In addition to pear trees and apple trees, psyllids settle on black currant bushes. Their foliage becomes covered with piebald spots, and a sooty fungus develops on the berries.
Maliciousness
Colonies of psyllids settle only on young parts of the tree where active vegetation is in progress. Sexually mature individuals damage the foliage by feeding on its sap. The greatest harm is caused by the larvae of the copperhead. Moreover, cultivated varieties for which the Ussuri or Pear-leaved pear was used as a rootstock suffer more severely. Varieties grafted onto wild plants are less susceptible to psyllid infestation.
After sucking the juice from young leaves, the nymphs secrete a sticky liquid called honeydew. If the colony of honey beetles is large, the liquid covers the entire foliage and sometimes drips onto the ground. The presence of honeydew and small insects on the underside of the leaves are the main sign of the presence of a dangerous pest on the pear.
Sooty fungus attaches to the sticky surface. This disrupts the process of photosynthesis. The foliage is drying up. The plant's immunity deteriorates. As a result, the tree cannot survive the winter normally and is often damaged by frost or dies. Flower buds damaged by pear honeydew dry out and fall off. Fruits that have time to set grow small and twisted. Their flesh loses its taste and becomes woody. Sticky secretions attract other pests and become a breeding ground for various fungi.
Important!
The copperhead is especially dangerous for young seedlings. On mature trees, damage to more than 25% of the crown by insects leads to a significant reduction in yield.
Signs of damage to the copperhead
A characteristic feature of the appearance of honeydews on a tree is the coating of shoots, leaves and buds affected by the pest with a sticky substance - honeydew. It is secreted by adults during feeding. Over time, honeydew spreads to all parts of the tree and covers the larvae. Larvae covered with secretions are protected from unfavorable external conditions.
If you do not get rid of the pest in time, this will lead to blackening of the foliage, fruits and shoots that were covered with honeydew.
Affected leaves and pears fall off prematurely. The harvest loses its marketable qualities - the pears become deformed and harden. Young branches dry out, and the tree itself weakens, loses frost resistance and the ability to bear fruit.
Pears affected by copperhead.
Fighting methods
The first procedure is carried out to destroy adult individuals after wintering. It is performed after the parasites emerge to the surface, before fresh foliage appears. Trees must be treated before females lay eggs. Usually the crown is sprayed in March after maintaining above-zero temperatures for several days. In frosty winters and late springs, treatment is postponed until early April.
To begin with, you can check the presence of copperheads on the fruit tree. To do this, spread a white cloth on the ground underneath and shake the plant. If there are insects, they fall onto the canvas. The effectiveness of the treatment performed is checked in the same way. The crown is sprayed in warm, windless and sunny weather.
Chemicals
If pear trees are heavily infested with psyllids, they cannot be dealt with without the use of chemicals. To combat them, pesticides containing organophosphorus components and oils are used. In this case, the drugs are alternated to avoid insects becoming accustomed to them. Solutions are prepared exactly according to the instructions, without exceeding the permissible dosage.
Before the first leaves appear, the trees are treated with the preparations “Aktara” and “Commander”. After flowering ends, spray again with Iskra or Agravertine. This time the most dangerous generation of suckers is being destroyed. Subsequently, after treating the garden plantings, the remaining psyllids die from codling moths or aphids. The last time trees are treated is in late summer or early autumn to reduce the number of overwintered individuals.
Advice!
The most effective treatment of plants is the day after heavy rain, when some of the honeydew is washed off from the leaves.
Biological agents
At home, pests can be controlled not only with chemicals. Neonicotinoids have a good effect. These are biological insecticides that, when used in large doses, provoke paralysis of the nervous system and death in the pest. They are very toxic to insects, but are almost harmless to humans and domestic animals. Often the products “Fitoverm”, “Lipidocid”, “Bitoxibacillin” are used for treatment.
Natural enemies
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Proponents of organic farming do not use chemicals to kill pests. In this case, one of the acceptable methods of control is to attract natural enemies of the parasites to the site. Artificial nests are built in trees to attract insect-eating birds. To destroy the parasite, forest bugs Anthocoris nemoralis are used. It can be purchased in special nurseries in 500 ml containers. Also useful for garden trees:
- fire beetles;
- lacewings;
- ladybugs;
- spiders;
- ground beetles;
- serphid flies.
To attract entomophages, plants that attract them are planted between trees:
- mustard;
- buckwheat;
- oats;
- legumes
Folk remedies
Remedies made according to folk recipes rid pear trees of pests only at the initial stage of their spread, when the number of colonies is small and little damage is done to the trees. When the flowering period is completed, the pear trees are fumigated with tobacco smoke. To do this, small piles of raw straw are made in the garden, after mixing it with tobacco crumbs, and set on fire. The rising smoke paralyzes the insects and they fall down.
Additionally, trees are sprayed with a decoction or infusion prepared from yarrow or dandelion herbs. Treating the crown with a soap or ash solution shows good results.
Natural enemies
A drop of honey to the terrible picture of tree damage will be the realization that honeymoon insects have many natural enemies that can protect our plants. Among the most important helpers we can distinguish such lovers of slow cooks as:
- coccinellids (aphid beetles);
- lacewings;
- syrphids.
All of them willingly eat psyllids, especially in the stage of young larvae. At the same time, we should not forget about such good friends of gardeners as five- and seven-spotted ladybugs.
To attract these beneficial bugs to the garden, annual legumes such as clover or alfalfa should be sown under trees. The cows develop on them, and after mowing the grasses, they begin to look for where to profit and find our copperheads on the fruit trees.
As always, at the end of the conversation we present a video about protecting fruit trees from pests:
Prevention
To protect the garden from diseases and insect infestation, choose a suitable place for planting and carry out preliminary preparations. The health and development of pear trees depends on many factors, including soil composition, acidity level, the presence of weeds, and the depth of groundwater. When choosing seedlings for the garden, it is better to buy varieties adapted to local conditions. They have stronger immunity. Therefore, they are less susceptible to insect infestation.
To prevent infection with pear psyllids, carry out general sanitary measures:
- regularly perform formative and sanitary pruning of the crown;
- during the summer, when branches and leaves damaged by insects are found, they are cut off and destroyed;
- tree trunks are cleaned of moss, lichen, and loose bark;
- in autumn the trunks are protected from damage by hares, mice and other rodents, whitened and insulated;
- the soil in the tree trunk circle is dug up;
- pull out the weeds.
Preventive actions
Those who do not want to use strong means can be advised to regularly inspect trees to identify pests and not neglect sanitary measures. To prevent the appearance of copperhead on pears, you should:
- carry out preventive spraying of trees in spring and autumn;
- remove plant debris at the end of the season;
- in the fall, dig up the tree trunk circle;
- clear old bark and whiten tree trunks;
- attract beneficial insects and birds to the garden.
