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Hydrilla verticillata (L. f.) Royle
Water-thyme

Hydrilla verticillata
Copyright by: Keith A. Bradley

Family: Hydrocharitaceae

Group: Monocot

Substrate: Freshwater Aquatic

Habit: Herb

Perennation: Perennial

Native Range: Old World; an invasive weed elsewhere.

Map of select IRC data for peninsular Florida

FLEPPC Status: Category I Invasive

SOUTH FLORIDA Occurrence: Present

SOUTH FLORIDA Native Status: Not Native, Naturalized

SOUTH FLORIDA Cultivated Status: Assumed to be Cultivated

Comments: For more information and images, visit Florida Invasive Plant Species Mobile Field Guide (FLIP) or click on the Atlas of Florida Vascular Plants link below.

Other data on Hydrilla verticillata available from :

Hydrilla verticillata has been found in the following 21 conservation areas :
Occurrence Native Status
Arthur R. Marshall Loxahatchee National Wildlife Refuge Present Not Native, Naturalized
Big Cypress National Preserve Present Not Native, Naturalized
Bill Sadowski Park Present Not Native, Naturalized
Bonair Beach Parcel, Martin County Present Not Native, Naturalized
Delray Oaks Natural Area Present Not Native, Naturalized
Dupuis Reserve Present Not Native, Naturalized
Everglades and Francis S. Taylor Wildlife Management Area Present Not Native, Naturalized
Everglades National Park Assumed to be Present Not Native, Naturalized
Fern Forest Nature Center Present Not Native, Naturalized
Fuchs Hammock Preserve Present Not Native, Naturalized
Hickey Creek Mitigation Park Wildlife and Environmental Area Present Not Native, Naturalized
Hugh Taylor Birch State Park Present Not Native, Naturalized
Jonathan Dickinson State Park Present Not Native, Naturalized
Miramar Pineland Present Not Native, Naturalized
Nicodemus Slough Present Not Native, Naturalized
Picayune Strand State Forest Present Not Native, Naturalized
R. Hardy Matheson Preserve Present Not Native, Naturalized
Seabranch Preserve State Park Present Not Native, Naturalized
Sewell Park Present Not Native, Naturalized
Tree Tops Park Present Not Native, Naturalized
Yamato Scrub Natural Area Present Not Native, Naturalized

Hydrilla verticillata has been found in the following 7 counties :
Occurrence Native Status
Broward County Not Native, Naturalized
Collier County Not Native, Naturalized
Glades County Not Native, Naturalized
Hendry County Not Native, Naturalized
Martin County Not Native, Naturalized
Miami-Dade County Not Native, Naturalized
Palm Beach County Not Native, Naturalized

Hydrilla verticillata has been found in the following 11 habitats :
Blackwater Stream
Disturbed Wetland
Dome Swamp
Flatwoods/Prairie Lake
Floodplain Swamp
Marsh Lake
River Floodplain Lake
Sinkhole Lake
Slough
Strand Swamp
Swamp Lake

All Images:

Hydrilla verticillata
Copyright by: Keith A. Bradley