Leaf Gall
Abiotic or fungal
40 host plants
Last updated
Abnormal puckered or bulging growths form on leaves, caused by fungi or midge insects that create deformities affecting appearance. Most galls are purely cosmetic and don't threaten overall plant health or survival. Severe infections may benefit from pruning affected shoots to improve aesthetic appearance and reduce pest or disease inoculum for the next season.
Galls are abnormal growths triggered by the pathogen and cannot be reversed once formed. Prune out galled tissue when practical, cutting well below the affected area. Avoid wounding plants during maintenance, as many gall-forming organisms enter through fresh injuries. For severe or recurring gall problems, consider whether the species is well-suited to the site conditions, as stressed plants tend to be more susceptible.
Quick Reference
Management
Schedule irrigation applications to avoid excessive leaf wetness, especially in spring. | Make two applications, the first before budbreak in spring and the second 2 to 3 weeks later. | Byther Biology Leaf gall is caused by a fungus, and results in the formation of off-colored, thick,
Cultural Controls
- Pick and destroy thickened, fleshy leaves and flowers before the white fungal spores are present.
- Remove all old galls from plants prior to bloom and flushes of new growth.
- Space plants and prune to reduce humidity.
- Avoid overhead watering or limit it to times when the foliage can dry quickly.
- The variety 'Massachusetts' is reported to be resistant to leaf gall.