What is Cogon grass? A look into invasive species management in Alabama

Cogon grass grows along a pond.
Cogon grass grows along a pond.

Symoum Syfullah Priyo/Wikimedia Commons

Related Topics:
Biodiversity, Conservation

Have you ever walked through a garden nursery and seen the beautiful purple flowers of the Chinese wisteria? Many people would not think about the species’ origins, but this is actually an important question to consider as you are purchasing things like plants and animals just based on their appearance. Most do not question or even bat an eyelash when they purchase a plant that looks exotic and take it home to plant it in their personal garden because they think that it is harmless. Sadly, this is not the case.

Despite their intentions, the act of doing this can be detrimental. Invasive species, according to National Ocean Service, are species that are not native to the environment to which it has been relocated to and therefore causes ecological or economic harm. Though this is not people’s intention, many gardeners and people fascinated by exotic pets and plants contribute greatly to this problem. 

Tackling the cogon grass invasion

In Alabama, one of the most pernicious invasive plant species is cogon grass. The yellow-green grass features twelve to thirty inch long leaves and is endemic so much of Asia. It was first introduced to the United States in the early 1900s through a port in Mobile, Alabama.

Chuck Byrd, a land steward of the Nature Conservancy and a member of the Alabama Chapter of the Sierra Club, described the species as a “green cancer.”  One reason the species may be hard to manage is its unassuming appearance, as it is usually easily missed driving or even hiking in a park. 

According to Byrd, cogon grass was initially used as packing material and could be found in imports received in Mobile County. However, once this species was introduced, it took a life on its own and spread throughout Central and Northern Alabama and in more southern states like Mississippi and Florida.

The impact of its rapid spread has been felt by farmers across the South as the invasive species’ high silica content makes it tough for animals to eat, Byrd said. Silica is a mineral that is needed for plant growth and development that makes it hard for insects to fully digest the plant. This can be a problem because, if insects will not eat the plant or animals, the plant will just continuously grow, taking over the area it resides in.

According to Byrd, farmers have complained that even their goats will not eat it, which is drastic as most know that goats will eat almost anything. This poses a problem as the cogon grass is not only crowding out feed grass for livestock, but is also disrupting natural ecosystems across the state.  It chokes the growing and useful plants around it while also burning really hot when it comes into contact with fire, said Byrd. This can be detrimental to land, animals, and all types of people when the grass catches fires and spreads quickly, hurting farms, killing animals, and impacting communities with human deaths as well.

Management of the grass has been difficult, as the Alabama Forestry Commission notes that, “cogon grass is so widespread that eradication efforts are continuous, arduous, and expensive.”

Byrd explained that when he first began tackling the issue of cogon grass, he used a GPS device to scan the area and help identify where the invasive species were located. Byrd explained that when searching for invasive plants like cogon grass, they “used a handheld device like a phone or tablet to accurately track the location of the plant within a three to five meter area.”

Mapping shows where Cogon grass has been detected in the Cahaba River National Wildlife Refuge in Alabama in June, 2024. (Courtesy of Chuck Byrd)

To keep track of and analyze the data, Byrd uses geographic information systems. The technology helps mark what had been previously found, mark new sightings, and keep track of “what was treated, how it was treated, and when it was treated to make sure that the cluster was completely eradicated,” said Byrd.

Cogon grass is mapped using GPS technology. (Courtesy of Chuck Byrd)

He and his team also conducted extensive research on invasive species, like cogon grass. This has helped them identify which seasons the grass populates the most, as well as the easiest season during which to exterminate it, which was found to be August through October.

According to Byrd, the research he and his team conducted show that there are only certain times of the year when the seeds of the plant are noticeable and are fluffy in appearance which makes them easy to spot, but hard to treat as the seeds spread very easily.

Once he and his team have properly identified the cogon grass, they then spray the grass with herbicide. Byrd stressed that you do not want to overdo or under-spray the mixture, as too much could have no effect on the plant, and too little will not kill it at all and the chemicals have the potential to harm other nearby plants.

How can we help?

According to Byrd, residents of Alabama can support invasive species management by properly sanitizing themselves before adventuring out in nature and between moving locations.

This can be achieved by wiping yourself down, shaking your hair, and wiping your vehicle down as well as your pets. Byrd said that you could even reach out to your local park to see if they are helping with these efforts, noting that some parks are allowing people within the community to help the Nature Conservancy’s efforts by pulling the grass out of the ground. 

If you decide to buy a plant from the store, try to ensure it is native to your area. There is research that the extension services have provided to know which proper plants can be bought that will not hurt the species around it. “There are beautiful plants that Mother Nature has put in this environment for a reason and by buying those, it will positively impact our environment,” Byrd said.

How do you move the planet forward?
Submit Story

Get the Newsletter

Get inspiring stories to move the planet forward in your inbox!

Success! You have been added to the Planet FWD newsletter. Inspiring stories will be coming to your inbox soon.