Ringed silkworm: how a brown butterfly harms a garden and how to deal with it

The ringed silkworm is a seemingly unobtrusive butterfly that can cause enormous damage to trees. Despite this omnivorous nature, this apple tree, cherries, pears, plums and other fruit crops in the garden are especially affected by this extremely voracious pest.

Insect description

Ringed silkworm is a Latin species called Malacosoma neustria. According to the biological classification, he is a member of a large family of Cocoonworms, whose representatives are similar to each other in morphological characteristics (structure) and some behavioral features. The ringed silkworm is known as a malicious and ruthless pest of forests and garden plantings.

Males outwardly are very different from females: sexual dimorphism is pronounced, therefore, it will not be difficult to distinguish individuals of different sexes. The female is much larger than the male: she has a more powerful trunk, and her wingspan ranges from 3.6 cm to 4 cm. The main color of the butterfly is varied: from yellow with a touch of ocher to pale brown. The male’s wingspan is almost 1 cm less: its size is from 30 to 32 cm. This difference in size between individuals of different sexes is clearly visible. Males are colored in various shades of brown: from pale to red. On the wings of butterflies, there is usually a dark strip running obliquely, framed by a contour.

The color of males and females is often variable: it depends on the characteristics of the local population and environmental conditions.

The caterpillar of the ringed silkworm is quite large - up to 5.5 cm in length. She has a very beautiful and bright color: along the gray body are bright stripes: blue in the middle of the sides, as well as white, yellow, black and orange.

The habitat of the ringed silkworm is quite large: it extends to the forest zone of Europe and Asia. The butterfly is found in Russia, Ukraine, Belarus, Moldova, Asia Minor, where it is well known to gardeners as a pest of fruit trees.

Silkworm life

This butterfly prefers a nocturnal lifestyle. It keeps close to the power source of its caterpillars - wild and cultivated trees, so it is almost impossible to see it in the fields. Adults practically do not feed, wholly focusing on procreation.

Breeding

Soon after mating with the male, the female lays eggs. She does this immediately on thin branches of trees, the green of which is attractive from the points of view of nutrition for caterpillars. Usually a butterfly never flies deep into the crown, content with side knots, but at the same time trying to choose a secluded corner so that future offspring do not become a victim of birds or bad weather.

The masonry has the form of a ring covering a branch around it. The eggs are laid in neat rows. One female can lay about 500 eggs in her life, which remain to wait the winter until the heat returns.

With the beginning of spring, caterpillars are born.Usually this happens when the kidneys swell and the first young leaves appear, which will serve in the future to feed the voracious larva of the ringed silkworm. In the process of vital activity, the caterpillars secrete a sticky substance, forming whole clods of web. In a neglected case, it completely covers the affected tree, foreshadowing its imminent death. At night, the larvae begin to actively eat, gnawing buds, leaves and even buds.

When several molts pass as the caterpillar grows, the time for creating a cocoon begins. To do this, the larva weaves several leaves with silk thread, creating a shelter in it. It is in it that the transformation into a chrysalis occurs. In this state, the ringed silkworm will be from 10 to 15 days, after which (and usually this happens in the middle of summer) the pupa is transformed into an imago. Then the whole cycle is repeated again.

Causing harm

Only harming the bright, striped caterpillars of the ringed cocoon. They feed on leaves, and a decrease in the amount of greenery on a tree introduces an imbalance in the harmonious metabolism of plant nutrients, including disruption of photosynthesis vital for him. Sometimes the caterpillar population is capable of destroying entire young shoots. As a result, the tree weakens, ceases to bloom and does not bring a crop.

In order to prevent negative consequences for the garden, you need to start the fight against the ringed silkworm with the very beginning of spring. A careful inspection of the trees, with the search and subsequent destruction of the nests, will help to notice the dangerous pest in time.

How to deal with ringed silkworm?

So, the struggle with a butterfly begins immediately with the onset of spring. The first step will be the mechanical removal of egg clutches, and then the caterpillars:

1. First you need to carefully examine the trees on the site. If a masonry is found that rings a branch, then it must be completely cut off. Later, the leaves that feed on the striped butterfly larvae are also destroyed.
2. Branches cut together with the eggs of the pest must be destroyed as soon as possible by burning. Just throwing them away will not be enough: the caterpillars will still be born, and then with a high degree of probability they will move to neighboring trees in search of food.
3. All cobwebs must be removed from the tree.

These simple measures, if they do not completely save from the caterpillars of the ringed cocoonworm, but will certainly reduce their number in the future, therefore, mechanical removal should not be neglected.

Insecticides

Chemical insecticides show the best results in controlling silkworm caterpillars. But their use is justified only for infections of catastrophic proportions, because toxic drugs destroy beneficial insects, thereby violating harmony in the garden.

Insecticides are needed if:

• at the time of kidney swelling, 3 clutches were found;
• after the appearance of leaves from 10% of them are gnawed;
• when shaking most branches, 1-2 caterpillars or more fall to the ground.

It is rational to carry out spraying as early as possible, preferably at the very beginning of spring, while the buds have not yet blossomed. So most of the larvae found in the eggs will be dead.

For processing by spraying use:

• organophosphorus compounds (FOS) - are usually used on an industrial scale;
• neonicotinoids: Aktara, Calypso, Taboo, etc.
• pyrethroids.

Use any toxic drugs to control insects in full accordance with the instructions for use.

Biological methods

Against the already hatched caterpillars, the biological preparations Bitoxibacillin and Lepidocide are effective. Their main advantages are impact only on pests and safety (both for the inhabitants of the garden and for humans). These drugs work when the air temperature rises above 15 ° C.

Folk remedies

Gardeners use 3 non-traditional ways to control caterpillars:

1. Create special traps. The principle is that caterpillars often prefer to descend to the ground during the day.Therefore, the tree trunk is wrapped with a flap of fabric, fixed with a rope so that a lapel is obtained. During the day, the caterpillars are collected from it with gloves, because they can cause allergies. Also, a cloth smeared with sticky petroleum jelly can serve as a replacement for the trap: it will be impossible for larvae to get out of it.
2. Destruction of masonry when coated with kerosene immediately after detection.
3. Attraction of birds to the site, who gladly enjoy bright caterpillars: installation of birdhouses and feeders in the garden.

These methods are good when there are few eggs or caterpillars on the tree.

To expel the ringed silkworm from the site, you need to start a fight with its masonry immediately after winter. If there are too many eggs, then chemicals can not be dispensed with.