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- Unmatched silkworm
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- Damage to unpaired silkworms
One of the dangerous pests for cultural and forest representatives of the flora is an insect called unpaired silkworm. It is quite widespread in European and Asian countries, it can be found in the north of the American and African continents. This kind of caterpillars settled in Russia, occupying a vast territory of the country. It causes significant damage to plants, especially deciduous tree caterpillars. If insects do not have enough food, they move to coniferous young growth, and when they penetrate the nursery, they can cause serious damage to cultural plantings. If an unpaired silkworm eats needles due to the lack of other food, then for Siberian silkworm any conifers are the basis of the diet.
What is a pest?
Unpaired silkworm is a butterfly. It belongs to the family of burrows, the order - Lepidoptera. The insect got this name due to the fact that there are significant differences between females and males:
- the female has a thick massive abdomen, large wingspan, which can reach 75-90 mm;
- the male is the owner of a thin abdomen, and the maximum wingspan is only 40-57 mm;
- the female color is dirty white, the black lines of a zigzag shape are visible on them;
- the color of the wings of males is brownish-gray with a pattern in the form of intermittent dark stripes.
Even if you look at a photo of an unpaired silkworm inattentively, these differences are immediately evident. Butterflies are preferred in dry places with a rare forest, plenty of daylight. By the number of outbreaks of reproduction, the silkworm occupies a leading position among this type of pest.
Interesting!
The male can be recognized by the antennae. They have a dark gray color and an unusual structure, thanks to which a male individual is able to detect a female located at a distance of 11 km.
Unmatched silkworm at different stages of life
Heavy females fly infrequently. Mostly they spend time sitting on the tree bark. They attract males by the smell of external secretion products (pheromones), which are able to excrete. The most active unpaired silkworms are masculine in the evening. To find a mate, they are able to travel long distances.
After fertilization, the females lay eggs high on a tree under the bark. They are distinguished by a round shape, have a pink or yellow color. Females are very prolific, in one clutch there can be up to a thousand or more eggs. In this state, they spend a longer period of life, which reaches 8 months.
Interesting!
Opaque silkworm eggs are extremely resistant to frost and can withstand temperatures up to -50 ° C.
In spring, when the temperature rises to + 10 ° C, an unpaired silkworm caterpillar emerges from the egg. Her body is covered with air bubbles and bristles, which allows her to move with a gust of wind. If you need to travel long distances, unpaired silkworms release a web. The color of the body of the caterpillar that was born is light yellow. It quickly darkens and takes on black and brown tones.A characteristic feature is the presence on the body of several rows of warts. Touch these hairy caterpillars Hands are not recommended, as bristles can cause skin irritation.
The body of an unpaired silkworm caterpillar has a cylindrical shape, the length of which is from 40 to 80 mm. Her head is quite large, with 2 brown stripes on it.
Interesting!
The silkworm caterpillar is the only form of an unpaired insect that during energy accumulates energy for further phases of development.
As soon as the pests spread, they begin to actively search for food, as they are extremely voracious. The caterpillar of an unpaired silkworm eats foliage. Young individuals eat in the afternoon. Upon reaching 3-4 months, they feed at night, completely destroying the leaves. Also, caterpillars do not disdain young shoots, flowers and buds. The development cycle is 50-80 days and depends on climatic conditions.
After that, in the summertime (June-July) occurs pupation process. Dark brown mummy-like creatures reach a length of 20-30 mm. Rare tufts of hair are present on their body; hooks are located at its end. After 10-15 days, a butterfly appears from the pupa.
Interesting!
The development of an insect occurs at a temperature of + 20 to + 25 degrees. If it falls, development stops. Males survive 5 stages of the larva, females - 6.
What is dangerous silkworm
Unpaired silkworm causes significant harm to fruit trees and shrubs. Often gardeners have to fight caterpillars on the apple tree. Strawberries, cranberries, lingonberries and other cultivated cereals suffer from it. The immediate danger is caterpillars, eating buds, leaves and flowers. In only 2 months of its development, one individual is able to eat about 30 young leaves. If the caterpillars are in large numbers on the tree, they will leave the plant completely without foliage. This leads to his death.
Given that the silkworm makes 5-6 clutches, there is a serious threat to horticultural crops. To prevent this from happening, humanity has to constantly fight silkworms. For this, various methods are used, up to the manual collection of tracks. It is also recommended to apply preventive measures, which consist in processing trees with special means.
The benefits of silkworm
The silkworm not only brings harm to people, it also has significant benefits. During its existence, man has tamed and domesticated many animals. Insects also fell into this number, and among them there is silkworm. About 3 thousand years ago in China, it was first noticed that caterpillars have a unique ability - they make silk threads. Since then, the silkworm has been a domesticated insect that is completely dependent on humans.
The country "Celestial" for many years is famous for the production of quality silk. Sericulture has always been considered a profitable business. For its organization, an area with a mild climate is suitable, where a mulberry tree can grow. Its leaves are power source for silkworms. In Russia, they began to engage in sericulture relatively recently, but it was not widely used.
