Description and photo of a caterpillar and butterfly of the Siberian silkworm

Siberian silkworm is widely known to residents of the Ural, Siberian, Far Eastern regions. Caterpillar of the Siberian silkworm - a pest parasitizing on the needles. Prefers larch, less likely to suffer from the invasion of fir, spruce. With a large number of Siberian silkworm larvae on a tree, the plant stopsdevelop, needles turn yellow, fall off. Man has to take measures to fight butterflies and their caterpillars.

Appearance

The Siberian silkworm is a large butterfly with a wingspan of up to 80 mm (photo below). Males are different from females in smaller sizes, the presence of comb-like antennae. Coloring is yellowish-brown, brown, gray, black. On the front pair of wings patterns, light spots. Rear wings monochromatic colors. A photo of the Siberian silkworm at the imago stage is presented below.

Eggs of spherical shape, up to 2 mm in size (photo below). Initially the eggs are bluish-green, gradually changing color to brown.

Eggs, caterpillar and Siberian silkworm cocoon

On a note!

The colors may vary depending on where the female laid the egg - on the bark of trees, stalks, leaves. Siberian silkworm eggs are arranged in groups or one by one. Photos can be seen below. In one laying can be about 200 pieces.

Caterpillars of the Siberian silkworm are born miniature - about 2 mm. Eat well, grow quickly. At the last stage of development, the body length of the larva is 70 mm. The color varies from green to brown and almost black. On the body you can see the stripes of purple, specks.Caterpillars pass 4 molts, constantly increasing in size. Photos of the offspring of the butterfly can be seen below.

At the end of the development, the caterpillar of the Siberian silkworm turns into a pupa. Cocoon forms from silk thread, which itself produces. It clings to the bark of trees, stalk, leaves, freezes. Cocoon size up to 40 mm. Initially, the covers are light, then they acquire a brown shade, black, which can be clearly seen in the photo of the cocoon of the Siberian silkworm.

Development features

Caterpillar and butterfly of the Siberian silkworm

Years of butterflies begins in the second half of July, lasting about a month. Mating occurs on the fly. The male dies soon after fertilization, the female searches for a favorable place for laying eggs. Attaches them to the bark of trees, leaves with a special sticky substance that is released along with the eggs.

Development the larvae inside lasts up to 22 days, under favorable conditions, the young offspring of the Siberian silkworm appears already on day 13. Caterpillars of the first age actively feed on needles, grow quickly. In the period from August to September, significantly increase in size, compacted chitinous cover.Cycle on the photo. At the end of September, the caterpillars climb under the bark, forest litter, remain to winter.

With the onset of heat - in May, the larvae rise to the canopy, the whole warm season lives and feeds there. The second wintering of the caterpillar transferred in the fifth or sixth age. Development continues in May, by the end of June they pupate. The development of a butterfly in a cocoon lasts about a month. Externally - a motionless creature, inside - complex processes of transformation take place. In early September, young butterflies appear. Their task is to find a secluded place for wintering. Below is a photo of young animals.

On a note!

Development tracks occurs over a period of 2–3 years, while butterflies at the imago stage do not live for more than a month, do not eat anything. Energy reserves are enough to lay about 300 eggs at a time.

Sabotage

Caterpillars of the Siberian silkworm

The danger of the Siberian silkworm is not difficult to guess. Due to the fact that the development of the larvae is stretched for several years, and every spring they rise in the crowns, there is a risk of weakening the tree.

Butterflies spread their numerous offspring in different plants. In July, mass infection covers several million hectares of forest. This causes tremendous damage to forestry.The natural enemies of the Siberian silkworm are goldfish, bark beetles, and barbel. Photos can be seen below. Since bark beetles also cause harm to coniferous plantations, the scale of sabotage increases several times more. Insects are eaten by birds of prey.

In the mid-90s, the struggle with the larvae of the Siberian silkworm lasted 4 years. Then about 600 thousand hectares of forest area suffered from the pest infestation. Cedar trees died, which was of great value to the locals.

Over the past 100 years, 9 outbreaks of mass sabotage of silkworm caterpillars have been observed in Siberia. Stop reproduction succeeded through the use of modern insecticidal agents. Measures to combat the Siberian silkworm on the pine and other plants are taken continuously, if not to destroy the caterpillars, so to prevent their occurrence. Photos of mass destruction of plants are presented below.

Interesting!

Sericulture is especially developed in China. Natural silk, which is produced from yarns, is expensively valued. silkworm. Insects are specially bred on mulberry, provide all the necessary conditions for existence.Cocoons are harvested, preventing the butterflies from appearing. The length of the strings of one cocoon is about 900 m. Butterflies lead a sedentary lifestyle, they practically do not fly. The larvae are not dangerous to the surrounding plants.

Methods of struggle

Fighting Siberian silkworm

Caterpillars damage larch, oak, beech, birch, pine, spruce, aspen, fir, cedar, pearmaple Gypsy moth prefers deciduous trees, but not squeamish and conifers. The larvae of the first age feed on the day, as they grow up they move to a hidden lifestyle - they crawl out of the shelters at night.

The main control measures are:

• Collection and destruction of egg-laying. In small areas, young trees are scraped by hand, trampled down or thrown into the fire. Below is a photo of infected plants.
• In late autumn or in early spring, eggs are destroyed with the help of petroleum products - gasoline, kerosene, engine oil. However, it must always be remembered that these are combustible substances; if used improperly, the risk of a massive fire increases.
• Against the larvae use glue rings that are placed at a level of 1.5-2 m above the ground, which prevents pests from reaching the crown.
• In small areas, the caterpillars are harvested by hand, then destroyed by any method.
• The most effective method is insecticidal substances. Spray crowns, tree trunks. Processing is allowed to be carried out in early spring before flowering of trees or after. Actions poison enough for 20-45 days. Re-processing is carried out as needed.

Every autumn, spring, you need to carefully examine the bark of the trees for the presence of eggs, larvae, coat the trunks with a solution of lime, chalk. The life cycle of an insect covers several years, so the threat of infection is always there. Distribution to other trees occurs either in early spring or in late autumn. In the photo you should carefully consider the pest, then to respond to the problem in a timely manner.