Caterpillars – Leaf Feeding – Blueberry Field Guide

Caterpillars – Leaf Feeding

Bruce Spanworm and Winter Moth

(Operophtera bruceata & O. brumata)
Damage: Caterpillars feed in early spring on flower clusters, green berries and leaves.
Insect: Pale green caterpillars up to 18 mm long with two pale lines running the length of their body, with a pale green head. Moths fly in late fall and winter and lay eggs on blueberry plants. Larvae hatch in March and begin feeding inside buds and flower clusters until late May. They drop to the soil to pupate in June, where they remain until moth emergence after October. There is one generation per year.

Oblique Banded Leafroller

(Choristoneura rosaceana)
Damage: Caterpillars feed in early spring and mid-summer on flower clusters, green berries and leaves.
Insect: Small caterpillars overwinter on plants and begin to feed in early April inside rolled leaves or webbed flower clusters. Caterpillars are also present in July-August. Caterpillars grow to 25 mm in length, are pale green with black heads, and stay close to their protective leaf rolls when feeding. Larvae pupate within the leaf rolls, and tan coloured moths emerge in June and again in August. They can be seen fluttering around the bushes or resting on leaves. There are two generations per year.

Eye-spotted Budmoth

(Spilonota ocellana)
Damage: Caterpillars feed in early spring on buds, flower clusters, green berries, and leaves.
Insect: A dark brown caterpillar with a black head, 9 to 14 mm long. From March to May, caterpillars are found feeding inside flower clusters and leaves secured with webbing. Moths fly in June-July. Summer larvae feed on leaves and developing fruit from July to September, before overwintering as partially grown larvae. One generation per year.

European Leafroller

(Archips rosanus)
Damage: Caterpillars feed on flowers and developing fruit and leaves in spring.
Insect: Similar size and appearance as Oblique banded leafroller (OBLR), but European leafroller has only one generation per year whereas OBLR has two generations. European leafroller larvae appear later in the summer than OBLR. Moths fly in June-July and lay overwintering egg masses.