A very adaptable aquatic plant that can grow in a wide range of conditions, from fully submerged to dry soil. Cultivated as a source of edible tubers in some parts of the world, this Eurasian plant has proved a nuisance in many other countries, particularly when it grows in or near irrigation ditches. It is listed as a federal noxious weed.
OverviewOther names for this plant include:
- Common names: Chinese arrowhead, giant arrowhead, swamp-potato, old world arrowhead
- Scientific names: Sagittaria sagittifolia var. edulis; Sagittaria sagittifolia var. leucopetala; Sagittaria sinensis; Sagittaria trifolia; Sagittaria japonica
- This robust aquatic and wetland plant is related to our native arrowhead plants (Sagittaria latifolia, etc) but has become a pest in crop irrigation systems, drains and waterways around the globe.
- Hawaii arrowhead may rapidly overgrow fish ponds and influence the oxygen regime and environmental conditions in reservoirs, while its submerged vegetation can grow very thick, making access through water difficult.
Classification in Wisconsin: Prohibited
Species Assessment Groups (SAG) were assembled to recommend a legal classification for each species considered for NR 40. The recommendation for Hawaii Arrowhead was based upon this literature review developed by the department.
Leaves: There are three types of leaves produced by this plant, with longer ribbon-like green leaves growing under the surface of water, distinctive arrow-shaped leaves held above water on triangular stalks and intermediate floating leaves.
Flowers: Hawaii arrowhead flowers have three petals and three outer sepals. The petals are large and white, with a purple blotch at their base. They grow on a distinct stem that rises up from the root of the plant, with between 2-10 whorls of 3 flowers.
Fruits & seeds: Round seed heads are produced with many flat seeds held in winged sheaths. These seeds can float easily and travel great distances in moving water.
Roots: This plant produces stolons and rhizomes that spread in aquatic and wetland conditions, and the plant also produces tubers 2-5 cm long at the ends of root stems.
Stems: Are smooth and square or triangular-shaped.
Similar species: There is a range of native arrowhead species in Wisconsin, with the most common being broad-leaved arrowhead or Sagittaria latifolia. Broad-leaved arrowhead has broader leaves that are less sharply pointed than Hawaii arrowhead. Most native arrowheads lack the purple blotch located at the base of the flower petals with the exception of Sagittaria montevidensis; but this also has a "D" shaped cross-section to the stem as opposed to Hawaii arrowhead, which tends to have triangular-shaped cross-sections.
Currently, there have been no reports of Hawaii arrowhead in Wisconsin. Have you seen it? Send us a report.
Mechanical: Where there is a small or newly establishing population, the plant may be removed by digging out all parts of the plant, including rhizomes and any tubers.
Chemical: Aquatic approved herbicides require a permit.
View Hawaii arrowhead pictures in our photo gallery!