With the advent of May, a wonderful time begins in Russia, when cities are dressed up in bright greenery, the air is filled with the delicate aroma of flowering apple and bird cherry trees, and gardeners in summer cottages prepare their pets for the autumn harvest. But it happens that trees are chosen by various pests and people have to fight with them for the safety of green spaces. One such raider is the ermine moth. The insect has a number of characteristic features, each of which must be taken into account in the process of fighting it.
General Description
The term "ermine moth" biologists called the family of Lepidoptera mole-like butterflies. It includes about 600 species of different insects. Their dimensions are small: the wingspan is from six to twenty-eight millimeters. Such organisms live mainly in the tropics, but some species are also found in Russia.
Representatives of this family feed mainly on plants. Sometimes they can eat roots, more often - leaves. Caterpillars settle on the stem and leaves of trees, gradually entangling them with cobwebs. In this way, social nests are created, where insects pupate one at a time or by gluing several cocoons together. Several hundred caterpillars can live on one tree. Plants often cannot cope with so many residents and die. Feeding on a certain type of plant, the moth harms forestry and agriculture.
Common species
On the territory of Russia and neighboring countries, you can find about ten species of ermine moth. The greatest damage to forests and gardens is caused by insects that "specialize" in apple and bird cherry trees.
Apple ermine moth is found in the British Isles, in Sweden and Finland, in Siberia, as well as in Korea, Japan, in some areas of Canada and the USA. The caterpillars of this moth, dark yellow in color with black legs and spots, are also called "Mayworm" in some areas.
The bird-cherry ermine moth lives on a vast territory from the Caucasus to China. As in the case of the apple pest, it is very difficult to deal with this insect, since most chemicals are ineffective. After a few years, insects disappear due to natural factors, and damaged trees are completely restored. Of course, if you resist the pest, then this process will be significantly accelerated. Insects will stop attacking the plant in two or three years.
Moth outbreaks
In the European part of Russia, the ermine moth infects the trees of the Moscow and Leningrad regions. Outbreaks of activity of this pest were noted in the early 80s, in the mid-90s. In the late 90s, the trees of the Krasnoyarsk Territory suffered from it. ATIn the early 2000s, this moth appeared in Khanty-Mansiysk. In 2006, mass reproduction of the insect was observed in Sweden. In 2012, the epidemic began in Irkutsk. Every year the number of individuals increases, and this can lead to the fact that entire gardens and parts of forests will be infected. Despite the active fight against the pest, the next summer the moth returns again and destroys the trees with renewed vigor. The pest disappears only after a few years (from 2 to 5). At the same time, the struggle should become more and more pronounced every year, since animals could develop immunity to the previous means and preparations.
Insect Appearance
Ermine moth, the photo of which can be seen below, has a soft, but rather beautiful appearance. White butterflies with three to five rows of small black specks on the front wings live on the territory of Russia. The hind wings are grey, as are the undersides of the forewings. Their span is 20-26 mm. Butterflies are nocturnal.
The caterpillars of this insect are grayish-yellow in color, have black paws and a black head. Similar to butterfly wings, there are small specks on their sides.
Life cycle
The ermine moth lives for one year. At the end of summer, butterflies lay their eggs on the trunk of a fodder tree, covering them with a shield of protective mucus. Caterpillars hatch 3-4 weeks after laying and remain under the shield for the whole winter. There they feed on the shell of the eggs and partly on the bark. springthey move inside the leaves and eat them from the inside, leaving the outer shell intact. Growing up, the caterpillars move to the outer side of the leaf, creating a spider web above them.
At the end of May, the grown caterpillars create cobweb nests on the tops of trees, which gradually expand. At the beginning of summer, insects pupate. Cocoons are located in groups in the forks of branches. By the end of June, new butterflies are born.
Harming
An overgrown caterpillar colony can completely destroy a tree. But even if it doesn’t come to this, the apple or bird cherry tree, on which the ermine moth has settled, will be seriously damaged. Throughout their short life, the caterpillars destroy the leaves of the tree. First, they eat away the core (parenchyma) of tender young leaves, leaving only the outer shell. Without internal cells, the leaves cannot function, photosynthesis stops, the leaves dry, turn brown and fall off. Then, under the cobweb, insects continue to eat the crown of the tree, leaving the plant without a green cover. A plant that has lost its leaves cannot develop further, it slows down its growth, is not able to bloom and bear fruit. Subsequently, recovery may take more than one year.
In cities, the cause of pest control is not so much the likelihood of tree death as the aesthetically unsightly appearance of plants that were struck by ermine moth. Photos of such apple and bird cherry trees demonstratehow depressing and out of place they look on city streets.
Ways to control the pest
No matter how terrible the ermine moth is, there are methods to deal with it. If the affected tree is treated in a timely manner, it will not die and will continue to bloom and bear fruit after the recovery period. Treatment can be carried out with chemical insecticides, biological products based on a certain type of bacteria. You can also create pheromone traps that lure female moths. If the tree is not severely affected, you can manually collect nests and browned leaves. Once collected, they should be burned along with the caterpillars.
Features of chemical treatment
The fight against ermine moths can be carried out with the following insecticides: Parisian greens, arsenic solution or Bordeaux liquid. If there are no more than two nests on the tree, the preparations Lepidocid, Danadim, Bitoxibacillin can be used. For private gardening, it is recommended to use the Aktellik preparation, observing safety measures, since it is very toxic. Processing of trees is carried out strictly before or after flowering! The first treatment is carried out in early May. The cocoons can then be harvested from flowering trees by hand. In July, it is better to process the tree again, since it is at this time that the grown-up individuals begin to lay eggs.
Folk remedies
Not only professional biologists are developing means to combatinsect pests. Simple amateur gardeners can also tell you how to deal with ermine moth. For example, some summer residents recommend spraying trees with the following composition: a bag of red pepper, a pack of shag, one bottle of potassium permanganate are diluted in a bucket of water, and onion and garlic husks are added. The resulting mixture must be insisted for three days. If you do not want to prepare the composition, you can spray regular Coca-Cola on the trees.
Another popular way is not to pickle, but to catch pests. To do this, the tree trunk is wrapped with adhesive tape with the sticky side out. The adhesive tape needs to be changed as it fills with insects. Not only the ermine moth will fall into such a trap. The methods of struggle mentioned above are suitable for other insects. The attack of pests on plants is a natural process, the same as prolonged rains or a long heat wave. Timely organized actions will help to save plants from any negative impacts. It must be remembered that pests should be constantly fought until they completely disappear. If this is not done, then the infected tree may die. And then the moth will move to other, still he althy plants, subsequently leading to their death.
