We are still trying to remove this invasive plant from our area. For those who are not familiar with it, beach vitex (Vitex rotundifolia) is a category I invasive plant in Florida. It is current listed as “invasive, not recommended”. This means you can still purchase it but recommend you do not.
Why is that?
Well, being an invasive species, it reproduces at a high rate, has few consumers, and causes an environmental issue wherever it grows. It has the potential to cause economic issues as well. Beach vitex is from Asia and was brought to the United States as an ornamental plant. In upland landscapes, it does not seem to be a problem. However, when first used in coastal dunes it began to show its ugly head. Vitex begins as a low growing vine and becomes a shrub over time. It produced a beautiful lavender blossom in spring but then produces millions of seeds in late summer and fall. The seeds are spread by birds and are viable in seawater for several months. Dispersed in this way, the plant spreads across both the Pensacola Beach and Gulf Breeze side of the Intracoastal Waterway.
Once established it forms a taproot with above ground rhizomes extending as far as 20 feet. It is allelopathic, meaning it produces chemical compounds that kill nearby plants and spreads to cover this new territory. This includes the common sea oat. Sea oats have a fibrous root system which are good at trapping sand and forming dunes. These dunes can protect properties during storm surge. Beach vitex, having a taproot system, are not as effective. Though we are not aware of any beach vitex growing on the fore dune, if it does it could impact sea turtle nesting. We are also not sure whether the local beach mice will eat these seeds. Thus, displacing sea oats could impact beach mice.
We currently know of one site in Ft. Pickens, two properties in Gulf Breeze, two in Navarre, four on Perdido Key and Perdido Bay, 24 within Naval Live Oaks in Gulf Breeze, and 38 on Pensacola Beach; 70 properties total. One of the properties in Gulf Breeze, and nine on Pensacola Beach (14%) have been removed or treated and have not returned. One property in Gulf Breeze, one in Ft. Pickens, two on Perdido Key and Perdido Bay, 20 on Pensacola Beach, and 24 in Naval Live Oaks (68%) have been removed or treated but have returned; re-treatments are required and are being conducted. And one property in Gulf Breeze, two in Navarre, two on Perdido Key or Perdido Bay, and nine on Pensacola Bay (20%) have not been removed or treated at all. In each of these cases, the plants are on private property. We hope that these property owners would consider removing the plant and replacing with native dune plants from this area.
Recently, volunteers from the Pensacola Beach Advocates and Americorp removed 315 m2 of beach vitex from public land on Pensacola Beach. That now means all beach vitex on public lands have been removed or treated. Science shows that repeated treatments may be required for up to five years to completely eradicate the plant from that property, but PBA and Americorp plan to assist Sea Grant with removing this plant from the area.
If you believe you have this plant and would like to learn how to manage it. Contact Rick O’Connor at the Escambia County Extension Office. (850) 475-5230 ext.111.