With the onset of May, a wonderful time begins in Russia, when cities are dressed up with bright greenery, the air is filled with the delicate aroma of blossoming apple trees and bird cherry trees, and in summer cottages, gardeners prepare their pets for the autumn harvest. But it happens that trees are favored by various pests and people have to join them in the struggle for the preservation of green spaces. One of these raiders is an ermine moth. The insect has a number of characteristic features, each of which must be taken into account in the process of combating it.
general description
The term "ermine moth" biologists called the family of Lepidoptera mole-shaped butterflies. It includes about 600 species of different insects. Their size is 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 the trees, gradually entangling them with a spider web. Thus, public nests are created where insects pupate one at a time or by gluing several cocoons together. Several hundreds of caterpillars can live on one tree. Plants often do not cope with so many residents and die. Eating a certain type of plant, the moth harms forestry and agriculture.
Common species
In Russia and neighboring countries, you can find about ten species of ermine moths. The greatest harm to forests and orchards is caused by insects that “specialize” in apple trees and bird cherry trees.
Apple ermine moth is found in the British Isles, Sweden and Finland, in Siberia, as well as in Korea, Japan, and in some areas of Canada and the USA. The caterpillars of this moth, dark yellow with black legs and spots, are also called the May Worm in some places.
Moth ermine bird cherry inhabits a vast territory from the Caucasus to China. As in the case of the apple pest, it is very difficult to fight 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 after two to three years.
Moth breeding outbreaks
In the European part of Russia, ermine moth infects trees in 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, trees of the Krasnoyarsk Territory suffered from it. In the early 2000s, this moth appeared in Khanty-Mansiysk. In 2006, insect breeding 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 an active fight against the pest, 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 with each year should become more pronounced, since immunity could develop in animals against the previous means and preparations.
Insect appearance
The ermine moth, the photo of which can be seen below, has a dull, but quite beautiful appearance. White butterflies live in Russia with three to five rows of small black specks on the front wings. The hind wings are grayed out, as is the lower front. Their range is 20-26 mm. Butterflies are nocturnal.
The caterpillars of this insect are painted in a grayish-yellow color, have black legs and a black head. Like the wings of butterflies, small specks are located on their sides.
Life cycle
Ermine mole lives for one year. At the end of summer, butterflies lay their eggs on the trunk of a fodder tree, covering them with a protective mucus shield. Caterpillars hatch 3-4 weeks after masonry and remain under the shield for the whole winter. There they feed on the shell of the eggs and partly on the bark. In spring, they move inside the leaves and eat them from the inside, leaving the outer shell intact. Growing up, the caterpillars move to the outside of the leaf, creating spider web above itself.
At the end of May, the grown caterpillars create nests from the cobweb on the tops of trees, which gradually expand. In early summer, insects pupate. Cocoons are arranged in groups in forked branches. By the end of June, new butterflies are born.
Harm
An overgrown colony of caterpillars can completely destroy a tree. But even if it does not come to that, the apple tree or bird cherry, on which the ermine moth has settled, will be seriously damaged. Throughout their short lives, caterpillars destroy the leaves of the tree. First, they eat out 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 leafless plant cannot develop further, it inhibits its growth, is not able to bloom and bear fruit. Subsequently, the restoration may take more than one year.
In cities, the cause of pest control is not so much the probability of the death of a tree, but the aesthetically unsightly appearance of plants that were affected by ermine moth. Photos of such apple trees and bird cherry trees demonstrate how depressing and inappropriate they look on city streets.
Pest Control Methods
No matter how terrible the ermine moth was, methods of dealing with it exist. If timely treatment of the affected tree is carried out, it will not die and will continue to bloom and bear fruit after the recovery period. Processing 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 affected much, you can manually collect the nests and brown leaves. After collection, they should be burned along with the tracks.
Features of chemical processing
The fight against ermine moth can be carried out with the following insecticides: Parisian herbs, arsenic solution or Bordeaux liquid. If there are no more than two nests on the tree, the preparations Lepidocide, Danadim, and Bitoxibacillin can be used. For private gardening, it is recommended to use the drug "Actellic", observing safety measures, as it is very toxic. Trees are treated strictly before or after flowering! The first processing is carried out in early May. Then cocoons can be collected from flowering trees manually. In July, it is better to process the tree again, since it was at this time that the grown individuals begin to lay eggs.
Folk remedies
Not only professional biologists are developing pest control products. How to deal with ermine moth, simple gardeners-amateurs can tell. For example, some summer residents recommend spraying the trees with the following composition: a bag of red pepper, a bundle of shag, one bottle of potassium permanganate and a husk of onion and garlic are added to a bucket of water. The resulting mixture must be insisted for three days. If there is no desire to prepare the composition, you can spray ordinary Coca-Cola on the trees.
Another popular way is not to pickle, but to catch individuals of pests. To do this, the tree trunk is wrapped with tape with the sticky side out. Scotch tape needs to be changed as it is filled with insects. Not only ermine moth will fall into such a trap. The control methods mentioned above are also suitable for other insects. Pest attack on plants is a natural process, the same as long rains or long heat. Timely organized actions will help to save from any negative effects of the plant. It must be remembered that pests should be constantly controlled until they completely disappear. If this is not done, then the infected tree may die. And after the mole will move to other, still healthy plants, subsequently leading to their death.