re c'J 1-1^-?? (X Extension Circularl263 /January 1988 $125 5Mf = O Managing Leafrollers ^ on Caneberries in Oregon A.L. Knight, R. LaLone, G.C. Fisher, and L.B. Coop fi. Two species of leafrolling caterpillars—the orange tortrix and the obliquebanded leafroller—infest caneberries in the Pacific Northwest. While they cause little direct damage to the fruits or canes, economic loss occurs because the larvae are often the main insect contaminant at harvest. This is particularly true of the orange tortrix on red raspberries; it's occasionally true of the obliquebanded leafroller on trailing berries. Machine-harvested berries often display the worst contamination. Another "worm" that commonly rolls leaves and attacks buds very early in the season is the larva of the winter moth. This worm is never a contaminant at harvest, and although it's often confused with these two leafrollers, it seldom causes enough damage before bloom to justify control. Identification (Color figures 1, 2, 3, 4, 5, 7, 8, and 9 appear on pages 4-5. Figure 6 appears on page 2.) Timely identification and monitoring of the "worms" present in your fields determine the need for, and effective timing of, insecticide applications. For example: 1. orange tortrix can be a major problem for all varieties of caneberries during the season; 2. obliquebanded leafroller is usually a problem only for the later season varieties such as marion-, boysen-, and evergreen blackberries; and 3. winter moth larvae are not present in fields during harvest, but a high population density in spring (8 or more larvae per hill) can cause economic damage through extensive feeding on the developing buds. Orange tortrix and obliquebanded leafroller larvae can be easily separated based on three characteristics: body color, color of head and shoulders, and size of full-grown larvae: Orange tortrix • body color ranges from straw to yellow green; • head and shoulders are tan to light brown; and • full-grown larvae may reach 3 /i " (figure 1). Obliquebanded leafroller • body color ranges from pale to deep green; • head and shoulders are brown to black; and • larvae may reach 1" (figure 2). Larvae of both species wiggle vigorously backward when disturbed, often hang from silk threads, and do not crawl in a looping manner. Winter moth larvae are distinctive from leafrollers. They are lime-green loopers with yellow to cream-green stripes along each side of the body. They have green heads, and their body length may reach 1" when full grown (figure 3). The larvae have only two pairs of stubby legs on their abdomen, but leafroller larvae have five pairs—four in the middle of the abdomen and one on the end. Larvae of winter moth usually crawl in a looping manner and do not wiggle backward when disturbed. Orange tortrix adults are small moths, about Vi " long with a wingspan of 5/8 ". Both sexes are brownish or buff colored with a saddle- or V-shaped darker brown area Alan L. Knight, project assistant, The Pennsylvania State University Fruit Research Laboratory, Biglerville, PA, and former graduate research assistant. Department of Entomology, Oregon State University; Rufus LaLone, consulting entomologist, Silverton, OR; Glenn C. Fisher, Extension entomology specialist, Oregon State University; and Leonard B. Coop, research associate, Department of Entomology, Oregon State University. The authors gratefully acknowledge financial assistance from the Oregon Caneberry Commission and the Washington Red Raspberry Commission in the preparation of this publication. ORGGON STATG UNIVGRSITY GXTGNSION SGRVICG THIS PUBLICATION IS OUT OF DATE. For most current information: http://extension.oregonstate.edu/catalog