Troy Evans, Great Smoky Mountains National Park, Bugwood.org
Description: an aquatic fern. Floating leaves are 0.5-1.5" (2.5-3.8 cm) long, oblong, and vary in color from green to gold to brown. The surfaces of the leaves have rows of arching hairs that look like little egg-beaters. When young, leaves are smaller and lie flat on the surface of the water.
Ecological Threat: After maturing, Salvinia molesta forms chains of leaves that run together to form thick mats on the surface of the water. These mats restrict oxygen and light availability causing the death of the primary producers and disrupting the aquatic food chain. Submerged fronds are 'stringy' and resemble roots. Salvinia molesta is on the Federal Noxious Weed List and can invade almost any type of aquatic system. The plant is native to South America and was first introduced into North America as an ornamental.
Biology & Spread: Plants reproduce by spores and by budding of broken stems or attached nodes.
In Oklahoma: As of 2021, Giant Salvinia has not been reported in Oklahoma, but there are records in Texas, Louisiana, and Arkansas, including counties adjacent to Oklahoma. The ease of transportation of vegetative reproductive material on boats and other equipment and its extremely the rapid growth make it a species that could quickly become a problem within the state once established. The current distribution of this invasive just to our south also indicates that our waterbodies will be suitable for the continued spread of Giant Salvinia.