The Tortrix Moth Caterpillars attack a wide range of trees and shrubs, but they create worse damage on Top fruit trees - Apples and Pears.
The small brown or green caterpillars roll the leaf edges together and spin fin web of silken threads to hold the leaf in its coiled position.
The caterpillars can then feed on the leaf tissue and the protective covering makes it difficult to control by spraying.
Sometimes known as the Summer Fruit moth, but there is also another moth that bears this common name. The moth is light brown in colour - almost orange at times, and is active during May-June.
With two generations each year, the first eggs are laid in May-June - normally in batches of 50-100 in a circular cluster. The eggs are normally transparent, so it is possible to see the development stage of the larvae - caterpillar - inside the egg. The black head of the caterpillar is normally visible just after eggs are laid.
The caterpillars that hatch, then feed on the leaves - often spinning them together into a roll for protection. The caterpillars also attack the fruit of apples and pears , causing considerable damage. The best way of control is to pick off the affected leaves. The caterpillar will either be visible , or hidden inside the leaf.
Tortrix Moth inside protective web, ready to emerge in September, then continue laying further eggs which will then overwinter as larvae in cracks and crevices of bark.
The caterpillars when mature, will reach up to 20mm in length, and reach this stage quite quickly from the egg stage - usually in just two to three weeks. The caterpillar then pupates into a cocoon inside a rolled/spun leaf, which then emerges into the second generation in the year during August-September.
The later batch of larvae, from the August-September moth generation tend to overwinter in a bark crevice, or fork of branch - ready to emerge the following May-June to start the process all over again.
It can be a severe pest of Apples, but also attacks Pears. Pheromone are sometimes used commercially to trap the flying moths, but not with a great deal of success.
Provado Systemic will do the trick - as will Bifenthrin if used as a contact insecticide.
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