Invasive Plants in Sebastian — Sebastian, Florida

Brazilian pepper is the invasive plant most often named in the public record for the Sebastian area, and it shares the ground with a longer list. On Pelican Island National Wildlife Refuge, the federal refuge in the Indian River Lagoon off Sebastian, the U.S. Fish and Wildlife Service conducts chemical and mechanical control of Brazilian pepper, melaleuca, air potato, rosary pea, guinea grass, Chinese tallow tree, cogon grass and Japanese climbing fern. The Service describes exotic, invasive and nuisance species as serious threats that displace native species, destroy habitat and disrupt ecological communities on the refuge.

Out on the water, a second invader joins Brazilian pepper. The Florida Department of Environmental Protection states that much of the vegetation on the spoil islands of the Indian River-Malabar to Vero Beach Aquatic Preserve, the state preserve covering the lagoon off Sebastian, is exotic, consisting primarily of Brazilian pepper and Australian pine. Those dredge-built islands, the refuge uplands and the lagoon shoreline between Sebastian Inlet and Wabasso are where most documented invasive plant work near Sebastian has taken place.

Scale is the first reason. The Florida Fish and Wildlife Conservation Commission describes Brazilian pepper as the most widespread of Florida nonnative invasive plant species, occupying more than 700,000 acres, and as a shrub-like tree typically 15 to 30 feet tall. FWC states that it forms dense closed canopy forests that shade out almost all other plant life, alter natural fire regimes and are considered poor habitat for native wildlife, the same pattern found on the spoil islands and disturbed uplands near Sebastian.

Its history explains its reach along the Indian River Lagoon. The UF/IFAS Indian River Research and Education Center states that Brazilian peppertree was first introduced into Florida around 1840 and again around 1890, as an ornamental valued for its winter crop of red fruit, which gave it the names Christmas berry and Florida holly. It was not recognized as a problem until the 1960s. Two types were introduced, from southeastern and northern coastal Brazil, and they are now extensively hybridized in the state.

Spread is driven by wildlife, which matters on a coast with Pelican Island and Sebastian Inlet State Park as bird magnets. FWC states that local dispersal is primarily by raccoons and opossums and that long-distance spread is carried by fruit-eating birds such as migratory American robins. The Indian River Research and Education Center adds that Brazilian peppertree is dioecious: only female trees produce fruit, and now that it is no longer sold as an ornamental, birds and small mammals account for most of its spread.

The spoil islands are the clearest case. The 1986 state management plan for the aquatic preserve counted close to 55 spoil islands in the lagoon and stated that vegetation on these islands is generally dominated by exotics such as Australian pine and Brazilian pepper, while the shoreline fringe is generally vegetated with mangroves and other native wetland plants. That split, exotic interiors with native edges, still describes many islands off Sebastian and Roseland, according to the current FDEP description.

On the barrier island across from Sebastian, Pelican Island National Wildlife Refuge manages invasive plants on its uplands; its public use areas sit on the Historic Jungle Trail 3.3 miles south of Sebastian Inlet. Shoreline sites at Sebastian Inlet State Park and the San Sebastian River State Buffer Preserve have also been the focus of removal work. The 1986 plan noted that the saltmarsh community along the lagoon can contain mangroves, cabbage palms and exotics mixed in with native vegetation, depending on tidal flooding and past ditching.

The largest documented volunteer effort ran from 2002 to 2004. The NOAA Restoration Center records that the Marine Resources Council, in partnership with FDEP and with volunteers, restored approximately 230 acres of shoreline through invasive species removal and native mangrove planting, at sites in the San Sebastian River State Buffer Preserve, Sebastian Inlet State Park and Pelican Island National Wildlife Refuge. The project was named the Pelican Island Wildlife Sanctuary Shoreline Restoration Project.

NOAA reports that sixty-five invasive removal events were conducted along the 4.5 mile stretch of the project site to remove Brazilian pepper, and that over 700 volunteers took part in more than 30 native planting events, logging 2,842 volunteer hours. Plant species recorded for the Indian River Lagoon project include red mangrove, buttonwood and seagrape. Partners listed include the Indian River Lagoon Program and FDEP.

Research aimed at Brazilian pepper statewide is run from the UF/IFAS Indian River Research and Education Center, which describes its biological control program as targeting the state most serious invasive plant. Four candidate agents have been studied at the UF/IFAS Norman C. Hayslip Biological Control Research and Containment Laboratory: the Brazilian pepper thrips (Pseudophilothrips ichini) and three Calophya species. Release permits for C. latiforceps and P. ichini were issued in June 2019.

According to the Indian River Research and Education Center, the Brazilian pepper thrips has already been released at parks and private ranches, and researchers have observed that it has begun to affect Brazilian peppertrees. The center states that scientists consider biological control the best way to control the species because it avoids expensive mechanical control and chemicals, and it maintains a map of thrips release sites across Florida. No Sebastian-specific release site was identified in the sources reviewed for this page.

State rules apply in Sebastian as elsewhere in Florida. FWC states that possession of Brazilian pepper with the intent to sell or plant is illegal in Florida without a special permit. UF/IFAS Gardening Solutions states that it is illegal to plant air potato, one of the species on the Pelican Island refuge control list, a twining vine whose stems can grow to 60 feet and that spreads from hundreds of bulbils. UF/IFAS advises that Brazilian pepper trees found in a landscape be removed, and that the plant can be controlled by cutting and treating the stump.

At the state level, FWC reports that beginning in the 1960s melaleuca and Brazilian pepper spread rapidly into south Florida conservation lands, that nonnative invasive plants now affect approximately 1.5 million acres of Florida, and that its invasive plant section oversees the largest program of its kind in the United States. For the lagoon off Sebastian, the 1986 aquatic preserve plan directed field staff to develop an exotic plant control and removal plan for Brazilian pepper, Australian pine and melaleuca. City of Sebastian code provisions on invasive species could not be verified from a fetchable public source for this page.