Unceremonious Arboreal Corrosive

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

The corrosive tree tree lives everywhere, but it is especially harmful in the steppe zone. The range of her taste preferences is formed by all kinds of deciduous trees and almost all fruit crops. True, this unceremonious beauty tries to give special preference only to apple trees. It is quite easy to notice trees inhabited by harmful parasites - they are given out by withering and drying out tips of shoots, as well as solid accumulations of excrement on the soil. And the moves made by caterpillars in the shoots and leaf stalks provoke their rapid drying. Often, damaged branches break off, contributing to a decrease in yield. If the damage is especially severe, the trees may dry out

Meet the pest

The corrosive tree is an intricately colored large butterfly. The size of female pests reaches from 60 to 65 mm, and males - about 50 mm. Both the front and back wings of the parasites are white. On top of them are scattered small oval specks of bluish shades, and on the dorsal side of the breasts of corrosive woodworms, six rather large spots of dark blue can be seen. White stripes run across their dark blue thick abdomens, and females have small ovipositor at the ends of the abdomens. As for the antennae, in males half of the antennae are feathery, and the antennae of the females are equipped with a whitish downy. Well, the legs of these unceremonious parasites are black and blue.

Oval eggs of corrosive woodworms reach about 1, 2 mm in size and are yellow in color. White caterpillars, often growing up to 60 mm, are painted in pinkish or yellowish tones and are endowed with black tubercles covered with short hairs. And the heads, anal and occipital plates of gluttonous parasites are colored dark brown. The length of the dark brownish cylindrical pupae is about 30 mm. Ten denticles can be seen at the tips of their abdomens, and between their peephole there is a clearly marked corneous process.

The wintering of caterpillars of the first and second instars takes place in processions cut through the wood. At the end of the second wintering, approximately from the second half of May, the caterpillars make vertical moves, expanding the outlet openings. In these passages, they subsequently pupate. And mass pupation of corrosive arboreal trees usually occurs in June-July. The development of pupae takes from fourteen to eighteen days, and before the butterflies emerge, they move out of the holes made.

The years of colorful butterflies starts in late June or early July and continues until the end of August. Unceremonious pests are most active at night and in the evening. Females, unlike extremely active males, are almost always inactive and inactive. Fertilized females lay eggs in fairly solid groups - from twenty to one hundred and fifty eggs in each heap. And pests can place them anywhere: on shoots or on buds, in old tunnels made by caterpillars, under the bark of drying branches and even on the ground. The total fertility of corrosive arboreal trees reaches two thousand eggs.

After nine or twelve days the caterpillars are reborn. They immediately crawl over the trees, often hanging on cobwebs, and the wind carries them over fairly substantial distances. By the way, in windy weather, the mass death of caterpillars often occurs.

Entering tree crowns, caterpillars instantly bite into young shoots and leaf petioles, making longitudinal passages in them. They often change their feeding places and as they grow, they gradually move from thin branches to thicker ones. Each caterpillar makes three or four moves closer to autumn. At the end of the first wintering, from April to the very autumn, they bite into the wood of skeletal branches and trunks, grinding single longitudinal passages directed upward. During their development, caterpillars have time to shed seven times.

How to fight

Approximately in August-September, all wilting and gradually drying up shoots should be cut and burned. The dead trees are also uprooted and burned.

If the garden is inhabited by corrosive arboreal trees rather weakly (up to ten percent of the total plantation area), you can destroy the attacking branches with trunks of caterpillars of the second year of life by injecting insecticides into their passages. The easiest way to do this is with a rubber bulb or a thin tip that is attached to a backpack sprayer instead of a sprayer. Spraying with insecticides will be especially effective during mass breeding of caterpillars.

In wet cool weather, many caterpillars die from various bacterial and fungal ailments. In addition, endoparasites often kill caterpillars. Tahina flies and ichneumonids from poaching are especially actively infecting corrosive arboreal trees.