About Calla palustris L.
Calla palustris L. is a rhizomatous herbaceous perennial plant that grows in bogs and ponds. Its leaves are rounded to heart-shaped, 6 to 12 centimeters (2+1⁄4 to 4+3⁄4 inches) long, 4 to 12 centimeters (1+1⁄2 to 4+3⁄4 inches) broad, and borne on a 10 to 20 centimeter (4 to 8 inch) petiole. It produces a greenish-yellow inflorescence on a spadix about 4 to 6 centimeters (1+1⁄2 to 2+1⁄4 inches) long, which is enclosed in a white spathe. Its fruit is a cluster of red berries, with each berry holding several seeds. Fresh Calla palustris L. is very poisonous due to its high oxalic acid content. However, like the rhizomes of Caladium, Colocasia, and Arum, its rhizome becomes edible after drying, grinding, leaching, and boiling. This species is native to cool temperate regions of the Northern Hemisphere, including central, eastern and northern Europe (from France and Norway eastward, not present in Britain), northern Asia, and northern North America (Alaska, Canada, and the northeastern contiguous United States).
