WSU Whatcom County Extension

Integrated Pest Management for Raspberries

Strawberry Crown Moth

(Synanthedon bibionipennis)

Insects and Invertebrates

 

Strawberry Crown Moth - Photo by Tom Murray

 

Symptoms

Strawberry Crown Moth (SCM) larvae feed on the outer crown and root surface of caneberry plants. Girdled canes can cause plants to become stunted and have poor vigor resulting in decreased yields.  

 

Identification

The Strawberry Crown Moth resembles a yellow jacket in color and flight pattern. Adults are clear winged moths, with a wingspan of about ¾ inch. The forewings are nearly opaque with dark bronze to almost black edges. The hind wings are transparent with dark veins and dark fringe. The abdomen is black and banded with yellow on the second, fifth and sixth segments. Mature larvae are about ¾ inch long, white, with a dark brown head.

 

Life History

The Strawberry Crown Moth is found throughout the western United States and British Columbia wherever strawberries are grown. It overwinters as larva in the crown of raspberry plants. They become active in April and May and feed for a short time before pupating in the crown in May and June. Adults emerge in approximately 3 weeks (June/July), mate and lay eggs on leaves around the crown of the plant. Eggs hatch in two weeks and the young larvae begin feeding on the outside of the crown and at the base of small roots. As larvae mature, they bore deeper into the crown and are found in the center of the crown after one month of feeding. There is one generation each year.

 

Monitoring

A very effective pheromone lure is widely available and is the primary way to monitor for this pest. Sticky traps should be placed in the field by early June. Place 1-2 traps per field depending on field size. Check traps twice per week to monitor for first flight and than once per week to track adult activity.

Scout 3-5 sites per field, depending on field size, watching for weakened areas showing signs of brittle or collapsed canes. Examine the crown and lower areas of canes for signs of boring. Evaluate 10-20 hills, spaced 3-5 hills apart and record the percentage of infested hills.

 

Thresholds and Management

No threshold or tolerance level available.

Unlike strawberries, SCM larvae feed on the outer crown and root surface of caneberries. Therefore they are susceptible to insecticide drenches. The same fall or spring drench used to control raspberry crown borer will also control SCM.

 

Resources

Washington State University, Small Fruit Pests: Biology, Diagnosis and Management
http://cru.cahe.wsu.edu/CEPublications/eb1388/eb1388.pdf

University of California, IPM Online, Pests in Gardens and Landscapes: Strawberry Crown Moth
http://www.ipm.ucdavis.edu/PMG/GARDEN/FRUIT/PESTS/strawcrmoth.html

University of California IPM Online, Pests in Gardens and Landscapes: Strawberry Crown Moth Life Cycle
http://www.ipm.ucdavis.edu/PMG/GARDEN/FRUIT/PESTS/LIFECYCLE/lcstrawbcrmoth.html

Photography by Tom Murray

Secondary content using h2 tag.

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Heading using the h3 tag

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

WSU Whatcom County Extension 1000 N. Forest St., Suite 201, Bellingham, WA 98225 (360) 778-5800 whatcom@wsu.edu