Drippy Dieback
Lonsdalea quercina subsp
13 host plants
Last updated
This profile synthesizes data from multiple published sources. Expert field review is in progress.
Drippy dieback causes branch death with characteristic dripping or sticky exudates. You notice branches dying back with gummy, oozing appearance. The condition appears stress-related or disease-induced. Prune out affected branches and provide proper tree care.
The most practical approach is to reduce the conditions drippy dieback needs to thrive. Prune for better airflow, water at the base rather than overhead, and remove infected material promptly. For high-value plants or recurring problems, preventive treatments timed to protect new growth during the infection window can make a measurable difference.
Quick Reference
Management
Spring through summer, coinciding with Allokermes galliformis scale activity. Crawler migration in May and female settlement on new growth creates the primary infection window. Bacterial ooze production peaks in July. Red oak species, particularly northern red oak (Quercus rubra), are most vulnerable. Disease is emergent and range is still being defined." # Source: USDA Forest Service Research; Plant Disease Journal (doi:10.1094/PDIS-12-18-2248-RE)
Scale insect presence; recent branch wounding; warm summer temperatures (ooze peaks July); susceptible red oak species (northern red oak most vulnerable)" # Source: USDA Forest Service Research; Plant Disease Journal
Cultural Controls
- Monitor and manage Allokermes galliformis scale populations to reduce the vector pathway for bacterial entry.
- Prune and remove branches with active cankers during dry weather to reduce inoculum sources. Destroy pruned material.
- Maintain overall tree vigor through proper watering, mulching, and avoiding compaction in the root zone. Stressed trees are more susceptible.