By Whitney Cranshaw, Colorado State University Cooperative Extension, Entomology
The currant sawfly (imported currantworm) is probably the most important pest of backyard currants and gooseberries. The caterpillar-like larvae have a voracious appetite and can rapidly defoliate plants. The larvae are a kind of creamy green color with prominent dark spots and usually they feed together in small groups. Damage typically originates in the center of the plant, on more shaded leaves, but ultimately can involve the entire shrub.
The eggs are elongate and white, laid along the leaf veins on the underside of leaves. Eggs should hatch in about 10-14 days and the newly hatched larvae chew small pinholes in the leaves.
Pyrethrins, insecticidal soaps, and some formulations are registered for control of insects on currant and work well on currant sawfly. Sevin is not registered for use on edible currants.
Photos: Judy Sedbrook
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010