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.
Foliage
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.
Flowers
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.
Fruit
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.