Hydrophyllum Occidentale, Western Waterleaf. The leaves provide the best way to distinguish hydrophyllum occidentale from similar species such as hydrophyllum fendleri; they are pinnately divided into an odd number (7 to 15) of leaflets, which have a relatively small number (2 to 4) of large, rounded teeth along the edges.
Waterleaf prefers shady sites. This native perennial prefers shady to partly shady sites (but tolerates full sun) and loamy soil rich in organic matter. It can be a good addition to woodland gardens but spreads aggressively, so is not a great choice for small landscapes.