Florida FWC Class I Prohibited Aquatic Plants: complete identification guide
Florida lists six aquatic plants as Class I Prohibited under FAC 5B-64. Here's how to identify each in the field, why they're dangerous, and what the regulations actually require.
Florida Fish and Wildlife Conservation Commission (FWC) lists six aquatic plants as Class I Prohibited under FAC 62-304.600. These species are banned because they establish rapidly, outcompete natives, degrade habitat, and spread through recreational watercraft and equipment.
The six Class I Prohibited Plants
1. Hydrilla (Hydrilla verticillata)
ID: Submerged stems with whorls of 3–8 leaves per node. Leaves are 6–8 mm long with fine teeth on edges (feels rough). Turions (potato-like reproductive organs) cluster at nodes and root.
Where it grows: Depths 2–15 feet. Forms dense canopies that top out at the surface.
Why it's dangerous: Hydrilla reproduces through fragmentation, turions, and root tubers — a single plant fragment can establish a new population. It outcompetes all natives, reduces oxygen, and damages boating and fishing.
Florida pressure: Established statewide. Harris Chain, Lake Apopka, Lake Kissimmee, and the St. Johns River system have documented dense beds.
Regulatory note: FWC regulates hydrilla through ERP (Environmental Resource Permit) processes on public and private waters. IFAS Extension publishes the definitive Hydrilla verticillata identification guide (HS216, Universtiy of Florida).
2. Water Hyacinth (Eichhornia crassipes)
ID: Free-floating rosettes. Leaf petioles (stems) are inflated and bulbous — they look like tiny soccer balls. Trailing fibrous root system, up to 12 inches long. Lavender flowers in a spiked inflorescence.
Where it grows: Surface, throughout the water column. Drifts with wind and current.
Why it's dangerous: Doubles in biomass every 8–12 days in summer. Floating mats block sunlight, create stagnant anoxic conditions underneath, and harbor disease vectors (mosquitoes). Single rosette can produce 1000+ offspring in a season.
Florida pressure: Chronic statewide. Harris Chain, Lake Monroe, Lake Jesup, and all lower St. Johns system lakes have recurring seasonal blooms.
Regulatory note: FDACS and FWC coordinate hyacinth management on public waters; private shoreline owners are responsible. See FWC's water hyacinth management summary.
3. Water Lettuce (Pistia stratiotes)
ID: Free-floating rosettes, 1–2 inches diameter. Leaves are velvety (not shiny like hyacinth petioles) and arranged in a tight funnel. Fuzzy trailing roots, 6–8 inches. Often mistaken for duckweed.
Where it grows: Surface, in calmer bays and inlets. Often paired with hyacinth.
Why it's dangerous: Like hyacinth, explosive reproduction. Creates dense mats. Primary difference: smaller profile makes it harder to control with boom systems — it slips through.
Florida pressure: Common on slow-moving rivers and impoundments. East Coast and South Florida prevalence higher than Central Florida.
Regulatory note: Not as widespread as hyacinth but treated with same urgency. Mechanical removal preferred over herbicide due to the mat's ability to survive partial spray coverage.
4. Brazilian Waterweed (Egeria densa)
ID: Submerged or nearly submerged. Dense clusters of thin, linear leaves (2–3 mm wide) arranged in whorls of 3 or 4 along the stem. Stems are fragile and fragment easily. When pulled, leaves fall off immediately — leaves in a handful, fragments in the water.
Where it grows: Deeper water, 1–6 feet. Tolerates cooler water than hydrilla. Prefers high-flow systems (rivers, canals).
Why it's dangerous: Extreme fragmentation potential. A single harvest operation can spread it through broken stem pieces. It carpets the substrate and blocks light.
Florida pressure: Established in the upper St. Johns system and some Panhandle springs. Less prevalent than hydrilla or hyacinth but growing.
Regulatory note: FWC tracks Brazilian waterweed through IFAS Extension. Guide to Brazilian waterweed (HS217, University of Florida). Special care required during mechanical removal to avoid fragmentation spread.
5. Asian Swamp Lily (Murdannia keisak)
ID: Terrestrial to semi-aquatic emergent. Upright stems, 6–12 inches. Linear leaves. Small pink or white flowers. Often found on pond edges, not in open water.
Where it grows: Shallow margins, mudflats, damp soil. Less common in water than the other five.
Why it's dangerous: Establishes on exposed shorelines and stormwater pond edges. Less aggressive than hyacinth/hydrilla but a vector for spread to new water bodies through equipment and runoff.
Florida pressure: Detected in South and Central Florida. Not yet widespread but monitored.
Regulatory note: Often overlooked because it doesn't form mats like hyacinth. FWC spotting reports are crucial for early detection.
6. Giant Salvinia (Salvinia molesta)
ID: Free-floating fern. Leaves are divided into three parts: two floating upper leaves and one submerged lower leaf that is feathery (roots are not true roots — they're modified leaves). No roots. Doubles in biomass every 3–5 days in optimal conditions.
Where it grows: Surface, throughout. Can form dense, floating "mats" several feet thick in still water.
Why it's dangerous: Fastest-growing aquatic invasive. Shades water completely, depletes oxygen. Extremely sensitive to herbicides — common control method is biological (weevil). Mechanical removal difficult because it fragments and re-establishes from tiny pieces.
Florida pressure: Localized but serious where present. South Florida prevalence. Not yet established in Central Florida but monitored.
Regulatory note: FWC coordinates with USDA on biological control (Cyrtobagous weevil) in some systems. Mechanical removal is risky — consult FWC before harvesting.
How to report a suspected Class I plant
If you identify a Class I Prohibited Aquatic Plant on a waterbody not previously listed, report it to:
- FWC Wildlife Alert: 1-888-404-FWCC
- St. Johns River WMD (if applicable): 904-329-4500
- Southwest Florida WMD: 352-796-7211
Report location (lake/river name, GPS if possible), species (include photo), and extent (small cluster vs. widespread). Early detection can prevent a population from establishing.
Practical field identification checklist
Is it floating or rooted?
- Floating: hyacinth, water lettuce, salvinia (check for three-part leaves)
- Rooted/submerged: hydrilla, Brazilian waterweed, (Asian swamp lily is emergent)
If floating, check the petioles:
- Bulbous inflated petioles → hyacinth
- Fuzzy velvety funnel → water lettuce
- Three-part feathery leaves → giant salvinia
If submerged, count leaves at each node:
- Whorls of 3–8 → hydrilla (check for rough-edged leaves)
- Whorls of 3–4 thin linear leaves → Brazilian waterweed (check for fragmentation)
Specimen collection: Always collect a specimen for positive ID, especially if you plan to report. Photograph in place, then carefully pull a sample without fragmenting. Bag separately to avoid cross-contamination.
Legal and practical next steps
- Identify with certainty — use the IFAS identification guides linked above
- Photograph and report if on a public waterbody or if you suspect it's spreading from your property
- Hire a licensed contractor — do not attempt mechanical removal of Class I plants without understanding fragmentation risk and disposal requirements
- Coordinate with FWC on larger infestations — there may be cost-share or permit-streamlining options
For mechanical removal on your private water body, see our aquatic weed removal services or contact us for a site visit. We are licensed across Central Florida and coordinate all removal work with FWC guidelines.
Frequently asked questions
What does 'Class I Prohibited' actually mean in Florida?
Under Florida Administrative Code 62-304.600 (FAC 5B-64), a Class I Prohibited Aquatic Plant cannot be legally possessed, imported, transported, or cultivated in Florida without an explicit permit from the Florida Department of Agriculture (FDACS). Finding one on your property does not mean you violated the law — allowing it to spread from your property intentionally does.
Can I mechanically remove a Class I plant without a permit?
Yes. Mechanical harvest of Class I prohibited plants on a private water body does not require a permit from FWC. You do need a permit to transport harvested plant material on a public road — most contractors haul to a permitted disposal facility.
Do all six Class I plants look the same in the field?
No. Hyacinth and water lettuce are both free-floating, but hyacinth has inflated petioles (leaf stems) that look like lily pads; water lettuce is smaller and has fuzzy roots. Hydrilla is submerged with whorls. Each requires different identification.
What is the penalty for illegal possession of a Class I plant?
Up to $500 for possession without a permit, and up to $5,000 for intentional introduction or cultivation. The law distinguishes between discovery and intent — finding hydrilla on your lake is not illegal; spreading it is.
Founder of Aquatic Cleanup. Florida-licensed aquatic-vegetation operator working private lakes, HOA retention ponds, and waterfront properties across Volusia, Lake, Seminole, and Orange counties.
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