Learn how Hillsborough County identifies, removes, and manages invasive plant species across its conservation parks and preserves
At Lower Green Swamp Nature Preserve in northeastern Hillsborough County, protecting the landscape is about more than preserving what is already there. It also means identifying and removing plants and animals that don't belong.
Hillsborough County's Environmental Lands Management division works across four regions of the County to protect and manage thousands of acres of conservation lands and preserves. One of the ongoing challenges is invasive species, which can spread quickly, crowd out native vegetation, and alter ecosystems that native wildlife depends on. However, the battle against invasive plants looks different depending on where you are.
Different habitats, different threats
In the southwest region of Hillsborough County, particularly in coastal habitats and mangrove areas, crews often encounter invasive plants such as Australian pine and Brazilian pepper. Brazilian pepper is one of Florida's most widespread invasive plants, with experts estimating the plant has colonized more than seven million acres across the state. Once established, invasive plants can spread rapidly and form dense areas that make it difficult for native plants to survive.
The challenges look different in the northeast region, including at Lower Green Swamp Nature Preserve. The Environmental Lands Management team there monitors and manages invasive species such as cogon grass, natal grass, lygodium, rosary pea, balsam apple, and many more. Rosary pea is a particularly concerning vine because it spreads easily and is highly poisonous. Each species presents its own challenge, which means there is no one-size-fits-all approach to invasive plant management.
How invasive plants change the ecosystem
Florida's natural habitats are already under pressure from habitat loss. Invasive plants create another challenge for the native plants and wildlife that depend on these ecosystems. When invasive plants take hold, they can crowd out native vegetation and change the natural processes that keep habitats healthy.
Fire is just one example. Prescribed fire is an important land-management tool used to maintain many of Florida's natural ecosystems. Invasive plants can disrupt that process in different ways. For example, Brazilian pepper does not burn well. When it becomes established in an area where prescribed fire would normally help maintain the habitat, the plant can interfere with the effectiveness of that natural management tool.
Cogon grass presents the opposite problem. The highly flammable invasive grass can burn too intensely, creating excessive heat during a fire. That intensity can damage the ecosystem and, in some cases, sterilize the soil, making it difficult for native plants to return.
Invasive aquatic plants can create another set of problems by taking over waterways, blocking water flow, and altering habitat for fish and other wildlife.
Native plants support native wildlife
The removal of invasive plants is about more than protecting the appearance of Hillsborough County's conservation lands. Native wildlife depends on plants for food, shelter, and survival. That relationship is especially important for native pollinators, many of which have highly specific relationships with the plants they feed on. When invasive plants replace native vegetation, they can disrupt those relationships throughout the food web. Protecting native plants helps protect the wildlife that depends on them, from insects and pollinators to birds and other animals that rely on healthy habitats.
Using the right tool for the job
Environmental Lands Management uses multiple strategies to manage invasive species, with the approach depending on the plant, the habitat, and the scale of the infestation.
Mechanical control can include methods such as mowing and other physical removal techniques. Prescribed fire can also be an important management tool when used to restore and maintain a natural habitat.
Biological control uses a natural enemy that specifically targets an invasive species. One example in Florida is the air potato beetle, which feeds on invasive air potato plants.
Cultural control focuses on preventing invasive species from becoming established in the first place. That can include educating the public about invasive plants and their impacts, as well as limiting or banning the sale of particularly harmful invasive plants and weeds.
Chemical control can include carefully selected herbicides designed for specific invasive plants. Different species respond to different treatment, making proper identification and the right management strategy essential. Often, the most effective approach combines multiple tools over time.
Removing invasive animals
Environmental Lands Management's work also includes responding to invasive animals found on County-managed lands. The County may report sightings of certain invasive species, including invasive lizards, to the appropriate agencies. Hillsborough County actively targets invasive feral hogs, contracting hog trappers to capture and remove them from natural areas.
Like invasive plants, invasive animals can damage habitats and create additional pressure on native species.
How residents can help
The battle against invasive species is not limited to Hillsborough County's conservation parks and preserves. Residents can play a role by learning which plants are invasive before purchasing them for landscaping or gardening. Even species not prohibited from sale can pose a risk if they escape into nearby natural areas. Residents can also report invasive species when they find them and avoid moving plants, seeds, or other material from one natural area to another. Every invasive plant prevented from becoming established can help protect the native landscapes that make Hillsborough County unique.
At places like Lower Green Swamp Nature Preserve, the work is ongoing. Crews in Hillsborough County's four Environmental Lands Management regions face different invasive species and different challenges. However, the mission remains the same. Protect the native landscape and wildlife that make Hillsborough County's conservation lands worth preserving.
Learn more about the work done by Hillsborough County's Conservation & Environmental Lands Management department. Stay up to date on news about Hillsborough's conservation parks and nature preserves by subscribing to the Trailblazer Newsletter.