Forest Pest Insects in North America: a Photographic Guide

Poplar leafcurl midge

Prodiplosis morrisi Gagné (Diptera: Cecidomyiidae)

Orientation to pest

The poplar leafcurl midge, Prodiplosis morrisi Gagné, is a native North American cecidomyiid fly that lays its eggs on developing cottonwood terminals. The larvae feed on surfaces of expanding leaves, causing them to curl into elongated, largely cylindrical shapes. Leaves may stay green with only curled edges turning brown, or leaf may be killed. With sufficient feeding, terminal shoots may become stunted or killed. Trees of all sizes may be attacked. There may be up to five or more generations per year. Each generation damages 1 to 2 whorls of leaves, and because there is a short period between generations, normal leaves alternate with damaged leaves. The many larvae that develop in each curled leaf drop to the soil beneath the tree to pupate. Larvae of the last generation overwinter in the soil.

Hosts commonly attacked

This midge attacks various species of Populus, including eastern cottonwood (Populus deltoides W. Bartram ex Humphry Marshall), quaking aspen (Populus tremuloides Michx.), and Populus hybrids are attacked.


This species is of greatest importance in the southern United States, in cottonwood plantations.

Images of poplar leafcurl midge

Injury to cottonwood seedling from poplar leafcurl midge James Solomon, USDA Forest Service, 768x512 / 1536x1024
Figure 1. Injury to cottonwood seedling from poplar leafcurl midge, Prodiplosis morrisi

Important biological control agents related to this pest species

No information is available on natural enemies of this species.

Web links for information on poplar leafcurl midge