Forms a flattened tooth-like or wedge shaped gall on the outside between the cup and the acorn with the ends more or less protruding. It lies in a depression and is of a light brown color. Often there are as many as eight galls on a single acorn. It occurs on red, scarlet, black and scrub oak. According to H. F. Bassett the galls mature in autumn, and early in the spring following part becomes imagos, another part remaining in the larval state another year, while a few remain in this condition still longer, and, as suggested by C. V. Riley, may develop the third year.
Habitat: Ottawa, Can., Conn., N. Y., N. J., Penn., and westward.”
- William Beutenmuller: (1913) The North American acorn galls with descriptions of new species©