Submerged, bottom-rooted, stoloniferous, sprawling aquatic herb. Leaves are finely divided, feathery, arranged in whorls of 4-6 and heterophyllous. Flowers are minute, female and produced in September – February.
To help protect our environment:
Still or slow-moving water bodies.
Vegetative spread from rhizome and stem fragments, dispersed by water movement. Human-mediated dispersal through contamination of machinery, boats and equipment.
Displaces native plant species, decreasing native plant species’ richness. Decreases invertebrate abundance and diversity in invaded water bodies.
Follow up treated areas 3 times per year. Encourage natural regeneration of native plants or replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.
Do not attempt to undertake control of this species on Aotea/Great Barrier Island group. Please report to Auckland Council if seen on Aotea/Great Barrier Island group.
CAUTION: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.
Hornwort has forked leaves as opposed to the pinnate leaves of parrot's feather.
Parrot's feather has less than 12 leaflet pairs per leaf in comparison to E. water milfoil which usually has greater than 12.
Native milfoil is monoecious (males and females on the same plant), the exposed stems are usually pink coloured and the leaf tips which are acute rather than blunt ended.
