Hydrocleys nymphoides

Unwanted Organism, National Pest Plant Accord

• Water poppy

• Scientific Name: Hydrocleys nymphoides
• Origin: Native to tropical South America
• Type: Weed
• Plant Life-form Type: Floating-leaved
• Taxonomy: (Humb. et Bonpl.) Buchneau
• Presence: Locally naturalised, eradicated from most known sites, first record from Te Aroha, Waikato in 1914
• Habitat: Still and flowing water bodies
• Temperature (°C): Oct-22
• pH range: 6.8 - 7.2
• Hardness (ppm): 50 - 200
• Light: Strong
• Height: 100mm
• Difficulty: Easy
• Notes: Problem weed in still and flowing water bodies, poor dispersal capacity has limited spread. Introduced into NZ now an aggressive coloniser of ponds streams farm dams & lake margins to a depth of 2 metres. Found Rotorua Waikato Auckland Lake Rotoehu
• Propagation: Vegetative spread by stolon fragments, deliberate planting
• Features: Underwater stem is elastic, creeping, or floating near the water surface. Leaves and roots attached at each node along the stem. Leaf is a bright glossy green, oval, 7 cm long, and with an inflated main vein on the underside. The leaf sinus is shallow. Flowers consist of 3 yellow petals with a purple centre (filaments) and are up to 8 cm across.
• Source: TIFBIS
• Regional: Regional Pest Management Strategy: AUK, BOP, NTL, WKO.