hydrilla |
Plants: Aquatic |
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Liliopsida > Hydrocharitales > Hydrocharitaceae > Hydrilla verticillata (L. f.) Royle
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| Synonym(s): Florida elodea, water thyme, waterthyme |
| Hydrilla 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. 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. Hydrilla 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. Hydrilla 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. Hydrilla can sometimes be confused with Brazilian egeria (Ergeria densa Planch.) and Canadian waterweed (Elodea canadensis Michx.). The leaves of Canadian waterweed occur in whorls of three along the stem and are up to 0.2 in. (5 mm) wide. The midrib of Brazilian egeria is smooth as opposed to the toothed midrib of hydrilla. |
| Image |
Descriptor |
Description |
Photographer |
| 1149129 |
Control |
sprayer |
USDA APHIS PPQ Archive |
| 2132053 |
Dispersal |
tangled on boat motor |
Wilfredo Robles |
| 3694013 |
Feature(s) |
tubers |
Tim Murphy |
| 5400455 |
Foliage |
|
Graves Lovell |
| 5400456 |
Foliage |
|
Graves Lovell |
| 5400457 |
Foliage |
|
Graves Lovell |
| 5396743 |
Foliage |
|
Robert Vidéki |
| 5396744 |
Foliage |
|
Robert Vidéki |
| 5396745 |
Foliage |
|
Robert Vidéki |
| 5396746 |
Foliage |
|
Robert Vidéki |
| 5396747 |
Foliage |
|
Robert Vidéki |
| 5396748 |
Foliage |
|
Robert Vidéki |
| 5396749 |
Foliage |
|
Robert Vidéki |
| 5396750 |
Foliage |
|
Robert Vidéki |
| 5396751 |
Foliage |
|
Robert Vidéki |
| 5396752 |
Foliage |
|
Robert Vidéki |
| 5396753 |
Foliage |
|
Robert Vidéki |
| 5396754 |
Foliage |
|
Robert Vidéki |
| 5396755 |
Foliage |
|
Robert Vidéki |
| 5399023 |
Habitat |
|
Robert Vidéki |
| 5399030 |
Habitat |
|
Robert Vidéki |
| 5399031 |
Habitat |
|
Robert Vidéki |
| 2148040 |
Infestation |
|
Michael Frank |
| 1624024 |
Infestation |
Thick mats of introduced aquatic weeds interfere with recreational activities such as sailing and swimming. |
Richard S. Hammerschlag |
| 1624028 |
Infestation |
Discovered in the Crystal River in south Florida in 1960. |
Raghavan Charudattan |
| 1149120 |
Infestation |
|
USDA APHIS PPQ Archive |
| 1149124 |
Infestation |
|
USDA APHIS PPQ Archive |
| 1149125 |
Infestation |
|
USDA APHIS PPQ Archive |
| 5276057 |
Infestation |
|
Tony Pernas |
| 1149128 |
Infestation |
|
USDA APHIS PPQ Archive |
| 5345047 |
Infestation |
|
David J. Moorhead |
| 5392216 |
Infestation |
Infested river |
John M. Randall |
| 3694014 |
Infestation |
Jolly pond - Clayton Co. |
Tim Murphy |
| 5274078 |
Infestation |
|
Leslie J. Mehrhoff |
| 4064029 |
Infestation |
|
James R. Allison |
| 4064028 |
|
Wasissa Springs, Jefferson Co., Fla |
James R. Allison |
| 0002158 |
|
growing tip |
USDA ARS Archive |
| 0002159 |
|
heavy infestation, the rapid underwater growth "pushes" a portion of the mat above the water, giving the reservoir a field-like appearance |
USDA ARS Archive |
| 0002160 |
|
subsoil turions (tubers) at the end of horizontal stolons. These asexual reproductive structures are resistant to herbicides, and allow for rapid recolonization of a treated site |
USDA ARS Archive |
| 0002161 |
|
Joe Balciunas surveying for hydrilla agents (August 1983) at Lake Dal. Of the four agents approved for release two were shipped from India. |
USDA ARS Archive |
| 1148070 |
Plant(s) |
|
USDA APHIS PPQ Archive |
| 1148116 |
Plant(s) |
|
USDA APHIS PPQ Archive |
| 1149126 |
Plant(s) |
|
USDA APHIS PPQ Archive |
| 1149127 |
Plant(s) |
|
USDA APHIS PPQ Archive |
| 1624029 |
Plant(s) |
Discovered in the Crystal River in south Florida in 1960. |
Raghavan Charudattan |
| 2122079 |
Plant(s) |
|
Chris Evans |
| 2122080 |
Plant(s) |
|
Chris Evans |
| 2122081 |
Plant(s) |
|
Chris Evans |
| 1299189 |
Plant(s) |
|
Raghavan Charudattan |
| 5399032 |
Plant(s) |
habitat |
Robert Vidéki |
| 5399033 |
Plant(s) |
habitat |
Robert Vidéki |
| 5274079 |
Plant(s) |
|
Leslie J. Mehrhoff |
| 5274075 |
Plant(s) |
Whole plants out of water |
Leslie J. Mehrhoff |
| 5274076 |
Plant(s) |
Young plants |
Leslie J. Mehrhoff |
| 5274077 |
Plant(s) |
|
Leslie J. Mehrhoff |
| 5400454 |
Plant(s) |
|
Graves Lovell |
| 5345046 |
Plant(s) |
|
David J. Moorhead |
| 5400458 |
Plant(s) |
|
Graves Lovell |
| 5399513 |
Root(s) |
bulb |
Robert Vidéki |
| 5399514 |
Root(s) |
bulb |
Robert Vidéki |
| 5399494 |
Root(s) |
bulb |
Robert Vidéki |
| 5399495 |
Root(s) |
bulb |
Robert Vidéki |
| 5399496 |
Root(s) |
bulb |
Robert Vidéki |
| 5307063 |
Seed(s) |
|
Steve Hurst |
| 5399531 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399532 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399533 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399534 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399535 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399536 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399537 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399538 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399497 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399498 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
| 5399499 |
Twig(s)/Shoot(s) |
sprout |
Robert Vidéki |
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