Gall maker: Lasioptera solidaginis, a gall midge (Order Diptera, Family Cecidomyiidae).

Shape and Size: Called the "knotty goldenrod gall." May be roughly spherical to fusiform, with "eccentric" bulges.

Location: On stems of goldenrod (Solidago sp.) plants, summer. Approx. 3 cm in length.

Color: Color is the same as the overall stem structure.