giant salvinia
(Salvinia molesta D. S. Mitchell)

Overview

Appearance

Salvinia molesta is an aquatic fern that floats on the surface of the water. Submerged fronds are “stringy” and resemble roots.

Foliage

Floating leaves are 0.5-1.5 in. (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.

Flowers

This plant does not produce flowers.

Fruit

S. molesta reproduce by spores and by budding of broken stems or attached nodes.

Ecological Threat

After maturing, S. 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 death of the primary producers and disrupting the aquatic food chain. S. molesta is on the Federal Noxious Weed list and can invade most any type of aquatic system. The plant is native to South America and was first introduced into North America as an ornamental.

Resources

• Pest Alert - USDA APHIS PPQ
• Biological Control of Invasive Plants in the Eastern United States - USDA Forest Service
• Domestic Programs Pest Evaluation - USDA APHIS PPQ
• Federal Noxious Weed Disseminules of the U.S. - USDA-APHIS
• Global Invasive Species Database - Invasive Species Specialist Group
• Plant Invaders of Mid-Atlantic Natural Areas - National Park Service and U.S. Fish and Wildlife Service

Selected Images

Maps

Invasive Listing Sources

• Alabama Invasive Plant Council - Watch list A
• Alberta Fisheries Act
• Apalachicola Invasive Working Group
• Arizona Noxious Weeds
• Arkansas Noxious Weeds - Prohibited
• California Invasive Plant Council
• Colorado Noxious Weeds
• Connecticut Invasive Plant List
• Connecticut Invasive Plant Working Group
• Connecticut Noxious Weeds
• Federal Noxious Weeds
• Florida Noxious Weeds
• Georgia Exotic Pest Plant Council - Category 1 Alert
• Idaho Noxious Weeds
• Indiana Invasive Species Council - Invasive Plant List
• Indiana Pest Species
• Indiana Prohibited Plant Species
• Invasive Species of Concern in Georgia
• Maryland Aquatic Nuisance Species Plan
• Maryland Code and Regulations Nonative Aquatic Organisms
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Massachusetts Noxious Weeds
• Massachusetts Prohibited Plant List
• Michigan’s Prohibited and Restricted Species
• Mid-Atlantic Field Guide to Aquatic Invasive Species
• Minnesota DNR invasive species list
• Mississippi Noxious Weeds
• National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List
• National Park Service, National Capital Region Exotic Plant Management Team Invasive Plant List
• Nevada EDRR
• Nevada Noxious Weeds
• New Invaders of the Northeast and Northcentral
• New Invaders of the Southeast
• New Mexico Noxious Weeds
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Plant Invaders of Mid-Atlantic Natural Areas
• Rhode Island Natural History Survey
• South Carolina Illegal Aquatic Plants
• South Carolina Plant Pest List
• Tennessee Exotic Pest Plant Council
• Tennessee Noxious Weeds
• Treasure Coast Cooperative Invasive Species Mgmt. Area
• USDA APHIS Regulated Pest List
• Vermont Noxious Weeds
• Virginia Invasive Plant Species List
• Virginia Invasive Species Management Plan 2012
• Virginia Noxious Weeds
• Virginia Regulations for Enforcement of Noxious Weeds Law
• WeedUS - Database of Plants Invading Natural Areas in the United States
• Wisconsin Noxious Weeds
• Wisconsin's Invasive species rule – NR 40

References