University of Maryland Extension

Raspberry - Blackberry Insects

 1) Japanese Beetles

Japanese beetle on damaged leaf

Japanese beetles are metallic, coppery-brown and green, 1/4-inch-long beetles that often feed in large numbers, damaging the fruit and skeletonizing the foliage.

Control/Prevention - Spray Schedule

2) Brown Marmorated Stink Bugs

brown stink bug

3) Cane Borers 

The following three species of borers can infest brambles. No pesticide treatments are recommended. Prune damaged canes back into healthy wood. 

  • Raspberry cane borers make two girdling rings of punctures about 1/2-inch apart and within 6 inches of the shoot tip, causing the cane tip to wilt suddenly. The damage is quite visible but has little effect on the quality or quantity of the crop. 

small holes in cane from cane borer
Photo: Bruce Watt, University of 

raspberry cane borer damage to canes

black and orange cane borer
Photo: Jon Yuschock,



  • Raspberry crown borers can be very damaging to the bramble planting if not controlled. The large (1/2-inch to 3/4-inch) larvae tunnel into the base of the crown of the plant causing the canes to be stunted or to wither and die.

crown borer larvae inside cane
Photo:University of Georgia 
Plant Pathology , University of

Crown borer larva

black and yellow adult
Photo:University of Georgia Plant 
Pathology , University of Georgia,

Crown borer adult

  • Rednecked borers are insects that cause small to large gall-like swellings with split bark on the canes. Cane damage in the first year is more serious than damage to older canes because the wounds on younger canes provide a weakened spot for invasion by canker fungi and breakage by wind.

swelling on canes from borer
Photo: James Solomon, USDA Forest

Swellings on canes

rednecked cane borer
Photo: Susan Ellis,

Adult rednecked cane borer

Control/Prevention - Spray Schedule

 4) Sap Beetles and Yellowjackets

brown sap beetle
Photo: Joseph Berger,

sap beetle



Sap beetles and yellowjackets are extremely common and pose problems when they attack ripening fruits in large numbers. They feed largely on soft, overripe, and rotting fruits and vegetables and can be controlled by good sanitation in and around the planting and by harvesting ripe fruits regularly. Do not allow fruit to become overripe. For sap beetles, place plastic funnel traps (plastic soda bottles) in rows filled with vinegar, molasses, and water to capture this pest.

5) Spotted wing drosophila (SWD)Drosophila suzukii

adult spotted wing drosophila

 Control/Prevention - Spray Schedule


Control/Prevention - Spray Schedule

General Disease and Insect Pest Control Recommendations

Home Fruit Preventative Spray Schedule and Management of Common Problems

Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2020. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.