Leaf blotchminer

Various (Gracillariidae, Agromyzidae)

11 host plants

Last updated

Data Maturity Baseline

This profile contains verified pest data from extension databases. Regional field notes and expert review are in progress.

Leaf blotchminer larvae create large, irregular blotches within poplar leaves starting in mid-summer. The blotches appear as papery, brownish areas where the entire leaf tissue has been consumed by the larva developing inside. You notice these distinctive large mines contrasting sharply with remaining green leaf tissue. Heavy infestations cause significant defoliation and tree stress. The small larvae remain hidden within the blotches.

Monitor poplar foliage starting in June for early blotch formation. Remove heavily mined leaves by hand if populations are light; poplar tolerates some defoliation. For severe infestations on valuable trees, spinosad or neem oil applied to foliage targets young larvae. Repeat every 7 to 10 days. Maintain tree vigor through appropriate watering.

Quick Reference

Order
Various (Lepidoptera, Diptera)
Type
leafminer
Host Plants
11

Cultural Controls

Host Plants (11)

Populus alba White Poplar European White Poplar, Silver Poplar Populus angustifolia Narrowleaf Cottonwood, Mountain Cottonwood Populus balsamifera Balsam Poplar Populus canescens Gray Poplar Populus deltoides Eastern Cottonwood Populus fremontii Fremont Cottonwood, Western Cottonwood Populus grandidentata Bigtooth Aspen Populus nigra Black Poplar Populus tremula European Aspen European Trembling Aspen European Quaking Aspen Populus tremuloides Quaking Aspen Populus trichocarpa Black Cottonwood