Invasive plants can wreak havoc on local ecosystems, crowding out native species and disrupting natural habitats. Many states have banned the sale of these aggressive botanical invaders to protect their natural environment.
Florida, with its warm climate, is especially vulnerable to these green intruders that can quickly take over landscapes and waterways.
1. Brazilian Pepper Tree
Once popular in Florida landscapes, this South American native now dominates over 700,000 acres of Florida land. The deceptively pretty tree produces bright red berries and crowds out native vegetation with its dense canopy.
Wildlife can’t use it for food or shelter like they do with native plants. The sap can cause skin irritation and respiratory problems in sensitive people, making it both an environmental and health hazard.
2. Water Hyacinth
Floating on water with lavender flowers, water hyacinth might look innocent, but it’s actually a nightmare for waterways. A single plant can multiply into 60,000 new plants in just one growing season!
Originally from South America, this aquatic menace forms thick mats that block sunlight, deplete oxygen, and impede boat traffic. Florida spends millions annually fighting this purple-flowered invader that can completely clog lakes and rivers.
3. Melaleuca Tree
Paper bark trees, as they’re sometimes called, were brought to Florida in the early 1900s to help drain the Everglades. Boy, was that a mistake! Each tree can produce up to 20 million seeds per year that spread like wildfire.
Standing tall with spongy, peeling bark and bottle-brush flowers, these Australian natives suck up massive amounts of water and displace native cypress trees. They’ve transformed diverse wetland ecosystems into monotonous melaleuca forests across South Florida.
4. Kudzu Vine
Known as “the vine that ate the South,” kudzu grows at the astonishing rate of up to a foot per day during summer months. Introduced from Japan for erosion control, this climbing monster now blankets entire forests, utility poles, and abandoned buildings.
The massive root system makes kudzu nearly impossible to eradicate once established. While banned in Florida and many southern states, this green menace has already swallowed an estimated 7 million acres across the United States.
5. Hydrilla
Lurking beneath the water’s surface, hydrilla forms dense underwater forests that can grow an inch per day. Originally sold as an aquarium plant, it escaped into Florida’s waterways where it creates impenetrable mats that extend from the bottom to the surface.
Boat propellers get tangled in its stems, swimmers can become entangled, and native aquatic plants get shaded out. A single fragment can start a new infestation, making hydrilla one of the most difficult aquatic invaders to control.
6. Air Potato Vine
During summer months, this aggressive climber can grow 8 inches daily, quickly smothering native vegetation under its heart-shaped leaves. The bizarre “potatoes” are actually aerial tubers that drop to the ground and sprout new vines.
Native to tropical Asia, air potato vines can climb 70 feet high into tree canopies. Florida has found some success controlling this invader by releasing air potato leaf beetles, which feast specifically on this problematic plant without harming native species.
7. Chinese Tallow Tree
With attractive fall foliage and waxy white seeds that resemble popcorn, the Chinese tallow was once a popular landscape tree. Its milky sap contains toxins that can poison livestock and cause skin irritation in humans.
Each tree produces up to 100,000 seeds annually that birds spread far and wide. Once established, these trees form dense thickets that transform diverse forests into single-species stands, dramatically reducing wildlife habitat value across the southeastern United States.
8. Cogongrass
Hidden in plain sight, this innocent-looking grass with fluffy white seedheads is actually one of the world’s worst weeds. Accidentally introduced to Alabama in packing material from Japan, cogongrass now infests over 1.25 million acres across the Southeast.
The sharp-edged leaves contain silica crystals that can cut human skin and discourage wildlife grazing. Underground, its extensive rhizome network makes it nearly impossible to remove completely. Even worse, cogongrass burns hotter than native grasses, intensifying wildfires to dangerous levels.
9. Tropical Soda Apple
Armed with vicious thorns and marble-sized yellow fruits, tropical soda apple invaded Florida pastures in the 1980s. Cattle avoid the prickly plants but eat the fruits, spreading seeds across grazing lands through their manure.
Native to South America, this nightshade relative grows up to 6 feet tall and can form impenetrable thickets. The spiny stems and leaves make pastures unusable for grazing and can injure livestock. Florida ranchers have lost millions of acres of productive land to this thorny invader.
10. Old World Climbing Fern
Delicate-looking but devastatingly aggressive, this Asian fern climbs high into tree canopies and forms dense mats that smother entire forests. Wind-borne spores can travel for miles, starting new infestations far from the parent plant.
The fern creates “fire ladders” that carry flames into tree canopies during wildfires, killing trees that would normally survive. In Florida’s Everglades, this leafy invader transforms cypress swamps and pine flatwoods into fern-dominated landscapes where native plants cannot survive.
11. Carrotwood Tree
Sporting glossy leaves and unusual three-lobed orange seed pods, carrotwood trees were once popular in Florida landscapes. Native to Australia’s coastal regions, they’re perfectly adapted to thrive in Florida’s similar climate and salt-spray conditions.
Birds eagerly eat the bright orange fruits and spread seeds into natural areas. Once established in mangrove forests and coastal hammocks, carrotwood trees outcompete native vegetation for light and nutrients. Their dense shade prevents native seedlings from growing, gradually transforming diverse ecosystems into carrotwood monocultures.