HYGROPHILA

Hygrophila costata

LANDHOLDERS ARE RESPONSIBLE FOR CONTROLLING THIS WEED

Description

An upright plant that grows over a metre tall in shallow water. Forms dense mats along the edges of creeks and water bodies.

Leaves Up to 18 cm long and 5 cm wide, with a prominent midrib and hairy underside. Leaves grow in opposite pairs along the stem.

Flowers White or mauve, up to 9 mm long. Flowers are tube-shaped with five lobes and are sparsely hairy. Present in summer.

Fruit Capsules 7-13 mm long egg-shaped holding up to 20 seeds.

Seeds Tiny, pale brown round and flattened in shape. Become sticky when wet.

Stems Grow vertically and have a squarish cross-section. Are sometimes red to purple-ish in colour. Stems are branched lower down but rarely on the upper part of stems.

Dispersal Via seed and vegetatively.

Confused with Senegal tea plant (Gymnocoronis spilanthoides), East Indian hygrophilia (Hygrophilia polysperma) and Alligator weed (Alternanthera philoxeroides).

Control This is not a reportable weed. Manually remove where appropriate. Ensure all plant material is bagged and removed. Foliar spray with herbicide registered for aquatic use. Follow-up control is essential.