Perennial (sometimes annual for U. livida) aquatic herbs. Roots are absent. Stolons are long, branched, filamentous, bear tiny round bladders, and form dense sprawling mats. Bladders suck insect and zooplankton prey in when external hairs triggered. Flowers are submerged and borne in summer. U. gibba flowers are yellow and held above water. Seeds are small and ripen summer – autumn.
To help protect our environment:
Still and slow-moving water bodies, seasonally inundated water body margins.
Seeds dispersed by water movement. Vegetative spread from stem fragments, dispersed by attachment to waterfowl. Human-mediated dispersal through contamination of boats, equipment and aquarium/ornamental pond plants.
Spreads aggressively and forms dense mats, threatening small turf-forming species and native bladderwort species in freshwater ecosystems. May shade submerged vegetation and alter sediment chemistry.
Consider an aquatic pest plant control operator. Contact Auckland Council for control options.
CAUTION: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.