Pea Weevils & Pea MothUpdated: November 3rd, 2017Created: 25/07/12
There are two types of weevils
1. The Pea Weevil (Bruchus pisorum) which infests dry peas and beans in storage [no image] see https://calstock.org.uk/elf.php/2017/11/03/broad-bean-weevil
2. The Pea-leaf weevil (Sitona lineatus) is about 5mm long and native to Europe and survive on a wide range of cultivated and wild legume species.
They eat the young plants, obvious by the munched leaves, and the young stem can be completely eaten through, killing the plant. The Pea leaf larvae feed on the roots.
The pea moth (Cydia nigricana) lays eggs around the flowers and the very small larvae enter the young pods and feed until they tunnel out to pupate in the soils. It is olive brown colour with black and white bars on the front edge of its forewings and long antennae and 6mm long with a 12mm wingspan. Between 5 and 11 days after adult moths emerge they lay flat transparent/white eggs (size of a pinhead) on the leaves, pods, flowers or stems of pea plants.
After 1 to 3 weeks (depending on temperature) minute yellowish/white caterpillars with dark heads emerge. These migrate to and bore into young pea pods. Larval development lasts from 18 to 30 days after which the fully grown caterpillars (12mm) bore back out through pod walls and drop to the ground to spin cocoons containing particles of soil. They hibernate over the winter in these cocoons.