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.
1 Leaves simple, crenate (sometimes with a few basal lobes)
..2 Rays present, white; leaf blades 4-10 cm long, 1-2-pinnate (with 3-5 pairs of primary lobes)
..2 Rays absent (rarely present and very small, and then yellow); leaf blades 8-20 cm long, 2-3-pinnate (with 4-20+ pairs of primary lobes)