Birch Leafminer
Attacks:
All birch species
What you will see:
- Large blotch mines in the leaves
- Damage is scattered throughout the tree
- Mines will turn brown
- Leaves will look wilted
- High populations can damage the entire canopy
- Repeated defoliation by leaf miner will decrease tree health
- Leaf miner defoliation is directly correlated to Bronze birch borer attack
Life cycle:
- Pupae overwinter in a cocoon 1-2 inches under the soil
- Adults emerge in Spring (April-May)
- Mated females lay eggs in leaf (May)
- Larvae produce a blotch mine (May-June)
- Larvae form a pupation chamber in the soil (June)
Cultural practices:
- Water trees during dry season
- Plant birch in shady, cool, moist areas
- Reduce fertilization
- High nitrogen trees are more attractive to leafminers
- Mulch with Prescription Organic Matter©
- Plant flowers to provide nectar sources for parasitic wasps
Chemical treatments are effective in controlling the birch leafminer. Please consult with your Arborist for treatment recommendations.