Key Features
- Green to red bumps on leaves
- Distorted new growth
- Distorted leaves
Symptoms
Small wart like growth on the upper and lower leaf surfaces. Bumps start out green in early season, turning brownish black by the end of the season. Although galls rarely affect plant health, new leaves and new growth will be distorted in heavy infestations.
Biology
Small, cigar-shaped mites overwinter in cracks and crevices of the bark as inactive adults. As the buds swell in the early spring, they migrate out to the bud scales. When the buds open, mite feeding causes the newly developing leaves to form galls. Mites live, feed, and mate inside galls all summer. In the fall, mites move back to the bark before leaves drop.
Management Recommendations
Since this gall maker spends the winter as an adult on the plant, keeping old galls around will not contribute to future gall problems and may conserve natural enemies. Controls are not yet known for this pest.
Effective Pesticides
Pesticides are neither available nor recommended for managing this pest.
Resources
