Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.
..2 Inflorescence verticillate or umbellate-verticillate (when first developing sometimes appearing merely umbellate); leaves 1-15 cm wide.
....3 Inflorescence compound, the main inflorescence axis with nodes which produce verticils or umbels of pedicellate flowers, the inflorescence nodes also producing branches which themselves produce verticils or umbels of flowers; leaves (1-) 4-15 cm wide, the blade characteristically held in a vertical plane
....3 Inflorescence verticillate, all the flowers borne sessile or on pedicels on the unbranched inflorescence axis; leaves 1-6 cm wide, the blae usually more-or-less in a horizontal plane.
......4 Flowers and fruits pedicellate, the pedicels 1-10 mm long
1 Leaves not peltate, a sinus extending to the attachment of the petiole.
........5 Central leaf lobe notably more distinct than the other lobes (the sinuses on either side extending 1/3 to 3/4 of the way to the petiolar attachment); stems and petioles fleshy
........5 Central leaf lobe not more distinct than the other lobes (the sinuses on either side extending 1/10 to 1/4 the way to the petiolar attachment); stems and petioles filiform.
..........6 Fruiting umbels on peduncles 1-3 mm long; leaves 10-50 mm wide; [native of bogs, spray cliffs, and other wetlands]