Galls on Campus 2: Knopper galls

One of the most recognisable galls (on oak, at least) is the knopper gall, caused by the cynipid gall wasp Andricus quercuscalicis, and these galls have started to appear on campus (Figs 1-3) on acorns of Quercus robur.  Similar to … Continue reading Galls on Campus 2: Knopper galls