Spermatophytes (seed plants): Angiosperms (flowering plants): Monocots: Alismatales
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (2/10/25):
Hydrilla verticillata ssp. peregrina
FAMILY
Hydrocharitaceae
Go to FSUS key
Dig deeper at SERNEC, a consortium of southeastern herbaria.
Check out EDDMapS.org to see where this has been reported.
Hydrilla is most similar to Egeria, but it possesses prickles along the leaf margins and also on the central leaf vein beneath. Read more at Vascular Plants of North Carolina.
Aquatic weeds can clog irrigation channels and cover lakes, threatening crops and wildlife. Read more -- Outlawed! Federal Noxious Weeds: The Aquatics.
INCLUDED WITHIN
PLANTS NATIONAL DATABASE:
Hydrilla verticillata
FAMILY
Hydrocharitaceae
INCLUDED WITHIN Floristic Synthesis of North America. BONAP (Kartesz, 2021)
Hydrilla verticillata
INCLUDED WITHIN Flora of North America north of Mexico, vol. 22 (2000)
Hydrilla verticillata
INCLUDED WITHIN Aquatic & Wetland Plants of Southeastern US (Godfrey & Wooten, 1979 & 1981)
Hydrilla verticillata
COMMON NAME:
Wandering Hydrilla
To see larger pictures, click or hover over the thumbnails.
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JK Marlow jkm160914_166
September
SE-EPPC Aquatic Plant ID Workshop
Leaves of ssp. peregrina > 5× as long as wide (vs. those of ssp. verticillata shorter), per Weakley's Flora (2025).
)
JK Marlow jkm160914_166b
September
SE-EPPC Aquatic Plant ID Workshop
Leaves toothed with stout, sharp teeth on the margins; fresh leaves noticeably rough to the touch, per Weakley's Flora (2025).
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (2/10/25):
Hydrilla verticillata ssp. peregrina
FAMILY
Hydrocharitaceae
INCLUDED WITHIN
PLANTS NATIONAL DATABASE:
Hydrilla verticillata
FAMILY
Hydrocharitaceae
INCLUDED WITHIN
Floristic Synthesis of North America. BONAP (Kartesz, 2021)
Hydrilla verticillata
INCLUDED WITHIN
Flora of North America north of Mexico, vol. 22
Hydrilla verticillata
INCLUDED WITHIN
Aquatic & Wetland Plants of Southeastern US (Godfrey & Wooten, 1979 & 1981)
Hydrilla verticillata
5027
Submersed aquatic (rooted); Forb
Perennial
Monoecious
Habitat: Ponds, lakes, rivers, often locally abundant. This species has become a serious aquatic weed, per Weakley's Flora
Non-native: Korea & adjacent China
Common in NC Piedmont (uncommon in NC Mtns & SC Piedmont, rare elsewhere in GA-NC-SC)
CLICK HERE to see a map, notes, and images from Weakley's Flora of the Southeastern US.
This plant is causing problems in natural areas outside its native range, according to authorities such as:
- Kentucky Exotic Pest Plant Council, 2013
- NC Department of Transportation
- SC Department of Natural Resources Aquatic Nuisance Species List, 2003
- SC List of Regulated Pest Plant Species, 2017
- Tennessee Exotic Pest Plant Council, 2009
- USDA Federal Noxious Weeds, 091820
- Virginia Department of Conservation and Recreation, 2014
IS THE PLANT "ARMED"?
Leaves have stout sharp teeth on margins and midrib beneath
LEAVES:
Simple
Whorls of 4-8
FLOWER:
Summer
Whitish sepals & translucent petals in female flowers, male reddish-brown
3 sepals in pistillate flowers
3 petals in pistillate flowers
Flowers solitary on elongate flexuous stalks
FRUIT:
Summer/Fall?
Capsule
TO LEARN MORE about this plant, look it up in a good book!
- Field Guide to Aquatic Plants of Alabama (Lovell, 2007) p42
- Invasive Plants, Guide to Identification, Impacts and Control (Kaufman & Kaufman, 2007) p429
- Invasive Exotic Plants of North Carolina (Smith, 2008) p054
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