Creeping vine from Japan threatens to take over beaches
It’s being called the “Kudzu of the Coast.” Japanese beach vitex, an invasive, salt-tolerant and fast-growing plant that has plagued the Carolinas for a dozen years, has reached Vero’s shores.
And just as the nefarious kudzu plant was an “experiment” by government agencies as part of a publicly-funded roadside vegetation project, the vitex species were reportedly introduced onto beaches by scientists tinkering with nature.
The intent was good – to rebuild and stabilize the shoreline devastated by hurricanes, including the monster Hurricane Hugo – but a quarter-century later, the plant is now making engineers all over the Southeastern United States scratch their heads wondering how to get rid of it.
Castaway Cove resident Debbie Hernandez first noticed the plant, which she describes as “bright green with waxy leaves and purplish-pinkish flowers,” growing under her dune crossover. She didn’t think much of it at first, and thought the flowers were attractive, but every time she returned to Vero after travels, she noticed the plant was thriving.
Actually, she said, taking over would be a better way to describe it.
She took a photo of her oceanfront home and, when she shared it with family members who had visited, the first thing they noticed was that the scraggly vine had overtaken the dune and, like something out of a sci-fi movie, seemed to be crawling down the beach.
Unlike the movies where the villainous vine wraps around victims’ ankles, this vine kills in a more insidious manner. It actually roots and spreads just underneath the surface of the sand, trapping sea turtle hatchlings or preventing mothers from laying their eggs.
“It grows outward like in fingers and then those intertwine with each other,” Hernandez said. “The root system is very deep for some of the more established plants.”
Over the past year or so, those “fingers” have extended far down the beach, “and in Castaway, we have a very wide beach. That’s one of the reasons we chose that area,” Hernandez said. Castaway Cove’s beach is what is called an accreting beach because, due to its geology, it catches drifting sand from beaches north of it, and it also benefits from North County and Sebastian Inlet beach renourishment projects.
The plant had become an issue of public concern in the Jacksonville area in the summer of 2014 when the Florida Times Union reported on it in its garden column.
“Records dating back to 1955 show the plant was introduced into the U.S. by the United States National Arboretum,” the article said. “No one seems to know what became of these first plants, but the species was reintroduced multiple times by other plant collectors. In the 1980s, it was planted along the North Carolina coast to help stabilize the dunes battered by hurricanes. Plants are touted to have excellent salt, wind and drought tolerance, plus have low fertility needs.”
Now 30 years after those plantings – when sea oats were reportedly scarce – more government intervention may be needed to rid beaches of the plant. Because of its pretty flowers, residents might prefer to leave it be, but the Carolinas have mounted coordinated efforts to get rid of it.
According to various North and South Carolina publications, a method similar to pepper busting of Brazilian Pepper trees has had about a 70 percent success rate. Simply, the tentacles of the plant must be removed and cut off as close as possible to where the plant began to root (if you can find it). An herbicide would then be applied carefully, and re-applied about a week later. Scientists are also working on potential methods of killing the seeds of the beach vitex to prevent spreading.
Indian River County Coastal Engineer James Gray responded to Hernandez, thanked her for making him aware of the vitex on her beach and said the county is studying the issue.
“We have investigated the beach vitex outcroppings in and around the Castaway Cove area. It does appear that this invasive plant, although patchy at this time period, is beginning to out-compete native dune vegetation,” Gray wrote in an email to Hernandez in August.
“Over the next few months our Coastal Division will be developing a dune plant fact card identifying native vs. invasive dune vegetation specific to our area. This hopefully will provide homeowners with information so they can become more aware of their surrounding and initiate programs to remove invasive vegetation and replace with native,” Gray said.
“We are now aware of this plant (thanks to you) and are looking into ways to control it,” Gray said.
But he included the caveat that no one should disturb any beach or dune plants during turtle season.
“Due to sea turtle nesting season we cannot disturb any dune vegetation without a Florida Department of Environmental Protection permit between March 1 and Oct. 31,” he said in the email.