PEST MANAGEMENT IN FOREST NURSERIES

MAJOR PESTS

CUTWORMS (Lepidoptera-Noctuidae)

The cutworms are mostly injurious to the conifers like deodar pines etc. in the month of March – April. They also attack seedlings of teak, casuarinas, cassia and cashew in plains during August to October. The fertilized female moth of this insect lays about 2000 eggs in small lots on the humus, stones, weeds and other plants. After 26 days, hatching takes place and the larvae known as cutworms, feed on the dry leaves and green vegetation. During day, these cutworms hide in burrows of 30 to 75 mm deep in soil. At night, the larvae come out from the burrows to feed on the seedlings by cutting through the stem at ground level. They rarely claim and cut down the plants which are too large in size. The full grown larva is smooth, having short hairs which measures about 40 mm in length. Important cutworm species are, Agrotis ipsilon, A.flammatro,A.segeturn, Laphygma exigua and Spodoptera litura.

CONTROL MEASURES

• The edges of the nursery beds, surroundings, transplant beds etc., should be kept clean from the weed.It prevents the egg laying of the moths.
• Collection of the larvae, while digging and then destroying them also reduce the population of cutworm.
• Irrigation or flooding of nurseries, allow the cutworms to come out from their tunnels and they can be collected and destroyed mechanically.
• The mother beds one dusted with a mixture of quick lime and ash. This checks attack of cutworm larvae.
• Dusting of quinolphos 1.5% @ 25kg/ha is found to be effective against the cutworms.