arrowhead, Hawaii arrowhead, Giant Arrowhead, Arrowhead, Old world arrowhead
- Sagittaria sagittifolia is native to Asia and Europe. It is a perennial aquatic herbaceous plant that has become a crop pest around the world. It is very hardy and frost resistant. S. sagittifolia is used in cultivation for the starchy walnut sized tubers it produces.
- The leaves of S. sagittifolia are held on triangular petioles that vary in length with the depth of the water in which the plant is growing. The hastate leaves are large, very glossy and stand high above the water’s surface. The early, submerged leaves are ribbon like.
- The white flowers of S. sagittifolia have three petals with a purple spot at their base. There are three flowers in each ring or whorl. The flowers are monoecious and are insect pollinated. S. sagittifolia flowers in mid-summer.
- Fruits are achenes and ripen through the fall. S. sagittifolia can also reproduce vegetatively from whole, immature plants and from the underground tubers. Its seeds can float easily allowing it to be carried long distances on water currents.
- Ecological Threat
- Sagittaria sagittifolia is a federally listed noxious weed. It has been introduced to Australia, South America and North America. S. sagittifolia has been reported in Mississippi. The USDA Pest Risk Assessments rates it as medium to high in overall pest risk potential. S. sagittifolia can be found from Sub-arctic to tropical latitudes.
- Global Invasive Species Database. Invasive Species Specialist Group (ISSG). IUCN Species Survival Commission.
- Weed Risk Assessment. Revised 2009. USDA, PPQ, APHIS.
- USDA NRCS PLANTS.
- USDA ARS GRIN.
Images from Bugwood.org