hydrilla
Hydrilla verticillata (L. f.) Royle
Description from Invasive.org
- Appearance
- Hydrilla verticillata is a submersed, rooted aquatic plant that can grow in water up to depths of 20 ft. (6.1 m). Plants can survive in depths up to 40 ft. (12 m) in non-turbid water.
- Foliage
- Leaves are whorled in bunches of 3-8, but most often with whorls of 5. The midribs of the leaves are reddish in color with the undersides having small, raised teeth. Leaves are 0.2-0.8 in. (5-20 mm) long, less than 0.1 in. (2 mm) wide and have serrated margins.
- Flowers
- Only the female flowers of this dioecious plant have been found in the United States, which means no viable seed are produced.
- Fruit
- Turions (stem tubers) are bud-like structures which can drop off the plant and successfully survive freezing or drought. Tubers from the rhizomes are another way these plants reproduce and increase their invasive potential.
- Ecological Threat
- Hydrilla verticillata forms dense mats at the surface of the water. The dense mats can restrict native vegetation, irrigation practices, recreation, hydroelectric production, and water flow. It can invade most slow-moving or still water systems. This plant is believed to be native to Asia or Africa, although it is widely spread across the globe. It was first introduced into North America as an aquarium plant in the 1950s.
Resources
- Fact Sheet - Ontarios Invading Species Awareness Program
- Biological Control of Invasive Plants in the Eastern United States - USDA Forest Service
- Southeast Exotic Pest Plant Council Invasive Plant Manual - SE-EPPC
- Element Stewardship Abstract - The Nature Conservancy
- Federal Noxious Weed Disseminules of the U.S. - USDA-APHIS
- Weed of the Week - USDA Forest Service
- 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 from Invasive.org
View All Images at Invasive.org
Plant(s)
USDA APHIS PPQ - Oxford, North Carolina , USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage
USDA APHIS PPQ - Oxford, North Carolina , USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage
Plant(s) Discovered in the Crystal River in south Florida in 1960.
Raghavan Charudattan, University of Florida, Bugwood.org
Additional Resolutions & Image Usage
Raghavan Charudattan, University of Florida, Bugwood.org
Additional Resolutions & Image Usage
Plant(s)
Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Additional Resolutions & Image Usage
Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Additional Resolutions & Image Usage
