Notifiable Organism, Unwanted Organism, National Pest Plant Accord
- Scientific Name: Menyanthes trifoliata
- Origin: Native to temperate Northern Hemisphere
- Type: Weed
- Plant Life-form Type: Marginal sprawling
- Taxonomy: Tournef.
- Presence: Nationally eradicated, first record from Darfield, Canterbury in 1976
- Habitat: Only found in an ornamental pond and irrigation race in New Zealand, found in nutrient poor waters in native range
- Notes: A potential sprawling emergent weed in peaty areas.
- Propagation: Spreads by seeds, stem extension, and fragmentation, Can establish rapidly from stem fragments. Seeds have not been seen in the field in New Zealand
- Features: Sprawling emergent perennial herb. Leaves appear in threes at the end of stems (like the leaves of broad bean). Leaflets are elliptical to obovate, 3-10 cm long, 1-5 cm wide, entire or sometimes coarsely toothed. Leaves are all basal, with the petiole bases arranged alternately on the creeping stem. Flowers have five petals, pinkish-white in colour, with long white hairs on the top surface. Flowers are about 2.5 cm across.
- Source: TIFBIS
- Regional: Regional Pest Management Strategy: AUK.