Calla is a
genus of flowering plant in the
family Araceae, containing the single species Calla
palustris. It is native to
cool temperate regions of the Northern
Hemisphere, in central, eastern and northern Europe, northern Asia and northern North
America. The plant is very poisonous when fresh due to its high oxalic acid content, but the rhizome is edible after drying, grinding, leaching and boiling. Source
