Invasive Species List/Aquatic Plants

This page contains information on aquatic plant species on the Invasive Species List. For more general information about the event, see Invasive Species.

Alligatorweed (Alternanthera philoxeroides)

 * Taxonomy:Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Eudicots; (Unranked)-Core eudicots; Order-Caryophyllales; Family-Amaranthaceae; Genus-Alternanthera; Species-A. philoxeroides

Identification Tips:

Anatomy:


 * Leaves: Opposite; no petiole; elliptically shaped


 * Flowers: Flower spike; no petals; five white or colorless sepals; white; cloverlike;


 * Fruit:


 * Seeds: One seed per flower


 * Misc/General: Hollow stems;


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when: Ballast water; Alabama, 1987;


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat): Southeastern US, California


 * Characteristics of new habitat: Damp soil in shallow standing water;

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem): Dense mats crowd out native species; impede recreational activities like boating, swimming, fishing;

Brazilian Waterweed (Egeria densa)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Monocots; Order-Alismatales; Family-Hydrocharitaceae; Genus-Egeria; Species-E. dense

Identification Tips: Bright green; bushy;

Anatomy:


 * Leaves: Bright green; four leaves per whorl;


 * Flowers: Three petaled; white flowers;


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when: Aquarium trade; Long Island, 1893;


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness: Cleaning boats when exiting water;


 * Damage (why it’s a problem): Crowds out native species; dense mats impede recreation

Caulerpa, Mediterranean Clone (Caulerpa taxifolia)

 * Taxonomy: Kingdom-Protista; Division-Chlorophyta; Class-Bryopsidophyceae; Order-Bryopsidales; Family-Caulerpaceae; Genus-Caulerpa; Species-C. taxifolia

Identification Tips:

Anatomy: Feathery branches; rubbery;


 * Leaves: Small;


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when: Through the aquarium trade; 2000;


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem): Crowds out native species; toxic (but not to humans);

Common Reed (Phragmites australis)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Monocots; (Unranked)-Commelinids; Order-Poales; Family-Poaceae; Subfamily-Arundinoideae; Tribe-Arundineae; Genus-Phragmites; Species-P. australis

Identification Tips:

Anatomy:


 * Leaves: Elongate


 * Flowers: Bushy; purple or golden;


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when: Ballast water; 18th or 19th century;


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness: Glyphosate; fire;


 * Damage (why it’s a problem): Crowds out native plants; blocks out light;

Curly Pondweed (Potamogeton crispus)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Monocots; Order-Alismatales; Family-Potamogetonaceae; Genus-Potamogeton; Species-P. crisps

Identification Tips:

Anatomy:


 * Leaves: Undulating; finely serrated; oblong; blue-green;


 * Flowers: Arranged on dense terminal spikes that rise a few inches above the surface of the water


 * Fruit:


 * Seeds:


 * Misc/General: Good waterfowl vegetation; turions bear appearance of small green/brown pinecones;


 * Adaptive anatomy: Strong rhizome anchoring system

Introduction:


 * How introduced: Where/when: Introduced in US waters by hobbyists in mid 1800s;


 * How spread:

Life Cycle: Generally first pondweed to emerge in spring, dies in mid-summer; actively grows in winter


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem): Dense mats interfere with recreation; reduces oxygen levels

Rock Snot (Didymosphenia geminata)

 * Taxonomy: Kingdom-Chromalveolata; Phylum-Heterokontophyta; Class-Bacillariophyceae; Order-Cymbellales; Family-Gomphonemataceae; Genus-Didymosphenia; Species-D. geminata

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


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Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Eurasian Watermilfoil (Myriophyllum spicatum)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Eudicots; (Unranked)-Core eudicots; Order-Saxifragales; Family-Haloragaceae; Genus-Myriophyllum; Species-M. spicatum

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Giant Reed (Arundo donax)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Monocots; (Unranked)-Commelinids; Order-Poales; Family-Poaceae; Subfamily-Arundinoideae; Tribe-Arundineae; Genus-Arundo; Species-A. donax

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


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 * Damage (why it’s a problem):

Giant Salvinia (Salvinia molesta)

 * Taxonomy: Kingdom-Plantae; Division-Pteridophyta; Class-Polypodiopsida / Pteridopsida (disputed); Order-Salviniales; Family-Salviniaceae; Genus-Salvinia; Species-S. molesta

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


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Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Hydrilla (Hydrilla verticillata)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Monocots; Class-Liliopsida; Order-Alismatales; Family-Hydrocharitaceae; Genus-Hydrilla; Species-H. verticillata

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Melaleuca (Melaleuca quinquenervia)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Eudicots; (Unranked)-Rosids; Order-Myrtales; Family-Myrtaceae; Genus-Melaleuca; Species-M. quinquenervia

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


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Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Purple Loosestrife (Lythrum salicaria)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Eudicots; Order-Myrtales; Family-Lythraceae; Genus-Lythrum; Species-L. salicaria

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


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Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Water Hyacinth (Eichhornia crassipes)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Monocots; (Unranked)-Commelinids; Order-Commelinales; Family-Pontederiaceae; Genus-Eichhornia; Species-E. crassipes

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Water Lettuce (Pistia stratiotes)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Monocots; Order-Alismatales; Family-Araceae; Subfamily-Aroideae; Tribe-Pistieae; Genus-Pistia; Species-P. stratiotes

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):

Water Spinach (Ipomoea aquatica)

 * Taxonomy: Kingdom-Plantae; (Unranked)-Angiosperms; (Unranked)-Eudicots; (Unranked)-Asterids; Order-Solanales; Family-Convolvulaceae; Genus-Ipomoea; Species-I. aquatica

Identification Tips:

Anatomy:


 * Leaves:


 * Flowers:


 * Fruit:


 * Seeds:


 * Misc/General:


 * Adaptive anatomy:

Introduction:


 * How introduced: Where/when:


 * How spread:

Life Cycle:


 * Seed:


 * Adult

Reproduction:


 * General Reproduction:


 * What makes it so good at reproducing?:

Ecology:


 * Behavior:


 * Niche:


 * Trophic Level:

Native habitat:


 * Characteristics of said habitat:

Where it’s a problem (“new” habitat):


 * Characteristics of new habitat:

Preventative measures:


 * Laws and effectiveness:


 * Control measures and effectiveness:


 * Damage (why it’s a problem):