Lives on cottonwood and other poplars. Young larvae are white or cream-colored and very flat, while older larvae are more cylindrical and 4 to 5 mm long. Moths have a wingspread of 6 to 17 mm and have elongated yellowish forewings with white cross bars and diagonal markings. Larvae appear in spring and pupate within the mines during July and August; adults emerge during August.
During early summer, larvae of blotchminers feed and construct irregularly shaped mines between upper and lower surfaces of leaves. By mid-summer these mines appear as blotches on leaves. Infested trees usually shed damaged leaves prematurely.
Spray leaves with chlorpyrifos or oxydemeton-methyl at first sign of mining.