Columbia Water-Meal

<em>Wolffia columbiana</em> is a diminutive aquatic flowering plant belonging to the family Araceae, widely recognized as one of the smallest known vascular plants on Earth. It inhabits still or slow-moving freshwater environments, including ponds, lakes, ditches, and quiet backwaters, where it floats freely at or just below the water surface. The species occurs across a broad geographic range spanning the Americas. As a rootless, leafless organism, <em>W. columbiana</em> consists of a tiny oval thallus, measuring only a fraction of a millimeter in diameter, which carries out photosynthesis directly through its green surface tissue. Reproduction is primarily vegetative, with daughter plants budding from a specialized pouch on the parent thallus, enabling rapid population expansion under favorable conditions. The species is assessed as Least Concern on the IUCN Red List, reflecting its wide distribution and tolerance of varied freshwater conditions.