A leaf edge fold causing a globular to near-spherical pseudogall surrounded by a flattened margin. The inducer seems to be on the upper side of the leaf, causing the leaf to fold over onto the upper side, with the globular portion of the gall bulging to either side or outward from the edge. The gall is hairless, translucent (apparently thin-walled?), and green-pink to red. Observed on Populus tremuloides from Montana to Maine in June and July. A cross-sectioned gall was found to contain a midge larva.