We’ve all heard about the kudzu vine; how it might overtake you if you stand in one place too long. Well, the kudzu is probably moving so fast because it’s running for its life from the cogon grass invasion.
Cogon grass (Imperata cylindrica) has been in Florida since the 1930’s and was initially introduced to evaluate its use as cattle forage and for erosion control. By the time its invasive nature was discovered it was too late to stop it and it is now ranked as one of the world’s worst weeds. Wherever it has established a foothold it has been to the detriment of native ecosystems.
Now, it has even invaded our coastal shores in Franklin County. During a recent field visit I was shocked to be shown a band of cogon grass growing just above the high tide line along St. Teresa Beach. I’ve seen it in many settings before but never this close to saltwater. This salty location just emphasizes the tough nature of the plant and how it is adapted to out compete many native species. Cogon grass maintains greater than 60% of its biomass underground in roots and rhizomes which gives it a distinct advantage for survival after fires, mowing and even spraying with herbicides. It can take 3-5 years of herbicide applications to kill out a stand.
Problems associated with establishment are numerous. The grass thrives with periodic fires and even creates a fire hazard in natural communities because it burns much hotter, with a higher flame height than native groundcovers. In the location mentioned above it is doing a good job of replacing many of the native wildflowers that are important to butterfly migrations along our coastline each fall.
The state Department of Agriculture is keenly aware of the consequences of its unchecked spread and conducts a program whereby property owners can apply for assistance. Use the resources at this website to identify cogon grass in the landscape and learn how to take steps to stop its spread. Your native communities would thank you if they could.
Author: Erik Lovestrand