An Unwanted Beach Visitor: Beach Vitex
Now that summer is in full swing, many of us are spending more time on our gorgeous Gulf beaches. Sea turtles are nesting and everyone gets excited at sightings of dolphins, sharks, and the Blue Angels. However, we have another recent visitor to our beaches, and this one isn’t spending money and renting condos. It has moved in from out-of-state and plans to stay, potentially wreaking havoc to our fragile beach dune ecosystems.
Florida is no stranger to invasive species. Reports and stories of pythons, popcorn trees, feral pigs, and others can be found everywhere. As a matter of fact, Florida and Hawaii have more problems with exotic plants and animals than any of the other states.
Beach Vitex (Vitex rotundifolia) is originally from the coastal areas of the western Pacific. It was brought to the United States by North Carolina State University in the 1980’s to restore dunes along coastal Carolina after severe storms. The plant is very salt and drought tolerant and performs well in direct sun and sandy soils; perfect for our coastal beaches. It grows about 3 feet tall and produces branches that extend along the surface of the sand over 60 feet from the tap-root. The flowers are lavender and found in the spring. By midsummer the flowers have dropped and pea-size dark fruit is produced. The fruit is also salt tolerant and can be carried by ocean currents as well as birds. The plant seemed a perfect choice for restoration projects.
And then it began to overgrow the primary dune system, choking the majority of the native plants including sea oats. The shrub size of the plant and the presence of vertical tap roots in lieu of fibrous ones did not suit it well as a dune forming plant; some studies found that it actually increased the erosion of some dune fields. Beach vitex releases allelopathic compounds, reducing the water content of the soil which stresses native plants thus reducing competition for space. And then there are the sea turtles. Evidence indicates that the growth of this plant over the primary dunes has made it difficult for female turtles to find nesting areas, while fast growing branches grow over incubating nests and make it difficult, if not impossible, for the hatchlings to emerge. The plant has become such a problem that it has been dubbed “Beach Kudzu” and there is a two-state task force to remove it.
Beach vitex has dispersed north to Virginia and south into Georgia. Currently it has been reported in only three Florida counties; Duval, Santa Rosa, and Escambia. Because of the few records in our state it is not currently listed as an invasive plant in Florida. The problem is, most biologists will tell you that the best way to eradicate an invasive species is to get it early. However most do not see the introduction of a new plant or animal as invasive until it becomes established and difficult to remove.
Natural Resource Agents with UF IFAS Extension are tracking the locations along the coast of the panhandle where this plant may exist. If you believe you may have it please let us know so that the location can be recorded. If you are interested in removing the plant we recommend cutting back to the tap-root. Dab the remaining tap-root with Round-Up. It is best if the remaining parts of the plant do not leave the property; if legal it is ok to burn. If you must transport it off the property we recommend it be dried on concrete and then double bagged before removing to the landfill. In many cases it may take several years to completely remove this plant. If you have any questions about this plant please call your local county Extension Office. Special thanks to Sea Grant Agent Rick O’Connor firstname.lastname@example.org for use of this article.