Fauna
Plant

Columbian Watermeal

Wolffia columbiana

Also known as Columbia Watermeal

Columbian watermeal ranks among the smallest flowering plants on Earth, drifting on calm freshwater surfaces as minute, rootless green spheres barely the size of a grain of sand. Individual fronds reproduce prolifically through vegetative budding, often multiplying within days to blanket entire ponds in emerald scum. In autumn, fronds store starch and sink to the pond bottom as overwintering turions, rising back to the surface when waters warm in spring.

AquaticFloatingMinute
Columbian Watermeal reference1 / 7
(c) Stefan.lefnaer, some rights reserved (CC BY-SA) · cc-by-sa
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preySunlight, Dissolved Nitrates, Dissolved Phosphates
Predators
  • Mallard
  • Grass Carp
  • Painted Turtle
ThreatsSevere water pollution, excessive herbicide application, and wetland drainage
HabitatsQuiet ponds, marshes, sloughs, and slow-moving streams
Life spanPerennial (individual fronds live weeks, colony persists indefinitely)
Classification
  1. OrderAlismatales
  2. FamilyAraceae
  3. GenusWolffia
  4. SpeciesWolffia columbiana
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
Responsible observation
  • Surface spotting: Search for fine, grainy green dustings floating across undisturbed backwaters and pond margins.
  • Macro inspection: Scoop a handful of water and inspect the fronds under a 10x hand lens to see their globular structure.
Related species
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