Dichotomous table for gallers on Oxyria digyna
by Hans Roskam
1a On leaves => 2
1b Flower buds almost globularly swollen. Perigone enlarged. Flesh-coloured spore masses in ovaries, also at base of stamens. Usually many diseased buds, clustered in inflorescence. Microbotryum vinosum
2a Leaf blade curved and distorted downwards at margin. Locally strongly curled, deep green. Philaenus spumarius
2b Leaf blade ± uniformly strongly curled and deflected. Aphis fabae