Sagittaria spp. (except S. teres)

Sagittaria spp.

Also known as:

Arrowhead

Family: Alismataceae

Origin: Various

Sagittaria leaves clustered low to the ground.
Herb less than 2m in height. Forms dense stands that displace native aquatic vegetation and traps sediment in water margins
Photo credit: NIWA

Regional Pest Management Plan (RPMP) status

  • National Pest Plant Accord Species
  • Whole region — Progressive containment, council delivered

View more about the RPMP statuses

General description

Emergent, perennial herbs < 2 m tall. Creeping stolons and/or rhizomes and/or tubers. Growth form can vary with level of submergence. S. subulata is smaller than other NZ species. S. montevidensis, S. platyphylla and S. subulata produce pale inflorescences in summer and the seeds ripen in autumn.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell Sagittaria spp. within the Auckland region. As S. montevidensis, S. platyphylla and S. sagittifolia are National Pest Plant Accord species, these restrictions also apply across the whole of New Zealand for these species.
  • You must not plant Sagittaria spp. within the Auckland region

Auckland Council will manage Sagittaria spp. at all sites where it is known to occur.

If you see Sagittaria spp. anywhere in the Auckland region, please report it to Auckland Council at pestfree@aucklandcouncil.govt.nz.

Habitats

Still or slow-moving water body margins < 1 m deep.

Dispersal

Some species set seed, dispersed by water movement, livestock and waterfowl. Vegetative spread from rhizomes and/or stolons and/or tubers. Human-mediated dispersal through movement of contaminated soil, machinery and equipment and deliberate plantings.

Impact on environment

Forms dense stands, displacing native aquatic vegetation. Traps sediment, infilling channels and blocking drainage ditches. Impedes recreational activities and may impact mauri of wai māori.

Control

Recommended approaches

Do not attempt to undertake control of this species. Please report to Auckland Council.