Leaf blotchminer

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.