Roseslugs Fact Sheet By Wayne Ohnesorg, Extension Educator Bristly roseslug larva found feeding on a climbing rose in Madison County, Nebraska.

Pest Identification & Damage

Common Name(s): Roseslug, bristly roseslug, and curled rose Scientific Name: aethiops (Fabricius) : Family . There are two other species, bristly roseslug ( difformis) and curled rose sawfly ( cinctus), that feed on roses and could be confused with E. aethiops. Identifying Characteristics for damaging Stage(s): Larvae are yellow-green in color and partially translucent showing their digestive tracts as a dark olive green. The head is colored yellow to yellow-orange. May be confused for Lepidoptera larvae, but can be distinguished by the number of prolegs present. Roseslug, bristly roseslug, and curled rose sawfly larvae have 7-8 pairs of prolegs. Roseslug larvae are smooth and shiny and do not have rings of white spots encircling the body as curled rose sawfly larvae do. Bristly roseslug larvae have numerous bristles covering their bodies. Mature roseslug larvae are ½ inch in length. Damage/Nature and Symptoms: Larvae feed at night on the upper and lower surfaces of rose leaves in between veins effectively skeletonizing the leaves. Mature larvae can chew holes through leaves.

Distribution and Life Cycle

Distribution: Roses slugs can be commonly found along the west coast and in the eastern US north of Florida and south of New York. West of Iowa to the Rocky Mountains roseslugs are an Rose leaves that have been fed on by roseslugs from occasional pest. Cedar County, NE Summary of Life Cycle: Roseslugs overwinter in the soil as a pupa. In spring, the adults emerge. Females lay eggs in the leaves near the edge of the leaflets. When the larvae hatch they skeletonize the surfaces of the leaves. Mature larvae can also chew holes in the leaves. When the larvae are fully mature they will leave the plant and burrow into the soil. They construct an earthen cell in which to pupate. There can be one generation or multiple generations each year depending on the species.

Management Methods

Inspection/Survey Methods: Visual inspection of rose plants looking for feeding damage. Non-Chemical Management Strategies: Small infestations can be picked off by hand with the larvae thrown into a bucket with soapy water. Larvae can be sprayed off of plants as they will be unable to crawl back up onto the plant. Chemical Management Strategies: When using insecticides make sure to cover both the topside and underside of the leaves. Insecticides with labels for home use are: acephate, bifenthrin, carbaryl, cyfluthrin, esfenvalerate, lambda-cyhalothrin, permethrin and spinosad. Horticultural oils and insecticidal soaps can also be used. Read and follow all label directions when using insecticides.

References: Anonymous A. and rose slugs. Texas A&M University Pest Profiles:Wasps. Accessed 4/6/2009 http://hortipm.tamu.edu/pestprofiles/chewing/sawflie/sawflie.html

Anonymous B. University of Maryland, Maryland Cooperative Extension HGIC Plant Diagnostic Web site. http://plantdiagnostics.umd.edu/level3.cfm?causeID=194

Anonymous. 1997. Pests of Roses: Defoliators/leaf feeders. University of Minnesota Extension website FO-06953. http://www.extension.umn.edu/distribution/horticulture/components/6953_01.html

Anonymous. 2003. University of Wisconsin Insect Highlights June 16,2003. http://www.entomology.wisc.edu/diaglab/03hilite/6_16.html

Day,E. 1996. European Rose Slugs. Virginia Tech Cooperative Extension website. Accessed 4/6/2009. http://www.ext.vt.edu/departments/entomology/factsheets/euroslug.html

Hahn, J. 2007. Watch Out For Roseslugs. University of Minnesota Yard and Garden News Vol. 9 No. 6, May 15, 2007. http://www.extension.umn.edu/yardandgarden/YGLNews/YGLNewsMay152007.html

McLeod-Scott, J. and J. Williamson. 2007. Rose and Related Pests. Clemson University Extension HGIC 2107. http://www.clemson.edu/extension/hgic/pests/plant_pests/flowers/hgic2107.html