Imported Currant Worm
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Imported Current Worms  Larvae of the imported current worm are green with black spots and a shiny black head, reaching 1 ¼ in(3cm) long when fully grown. Eggs are pale green/white and are about 1/32(1mm) long., and are laid on the underside of leaves along the main veins, usually down low in the middle of the bush. There are two or three generations per year with damage starting in April or May. Larvae of the third generation overwinter in cocoons in the soil. Susceptible Plants- Gooseberries, White, Red and Black Currents, Gooseberry Symptoms- The first symptoms of imported current damage are tiny holes in the leaves made by young larvae. Newly hatched larvae feed in the center of the bush for 1 to 2 weeks, then they progress outward. They can quickly strip a whole bush of foliage leaving only a skeleton of leaf veins. Repeating defoliation may reduce fruit production. Prevention and Control- The adult imported currant worm is a sawfly, and herein lies the problem in trying to control it with one of the most common garden biologicals, Bacillus thuringiensis, also known as Bt. There is a strain of Bacillus thuringiensis effective against caterpillars and one that controls fly larvae. Sawflies are neither caterpillars or flies and cannot be controlled with Bt. Biological Control- Species that will control the imported current larvae and adult stage sawflies are Caterpillar Parasites: Trichogramma species Insecticidal Control- When the eggs first hatch, the larvae are so tiny, it's almost impossible to see them. Bonide Insecticidal Soap Bonide Pyrethrin This formulation of naturally occurring pyrethrin is perfect for vegetable, fruit, and ornamental gardeners. However this product is highly to fish and aquatic life and should not be used near lakes, ponds and streams. Even natural and organic products can be harmful if improperly used Monterey Garden Insect Spray
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