Without question, Cogongrass is the most troublesome invasive plant that I (and my clients) deal with. Here in Northwest Florida, we have a lot of it, and it is very difficult to manage. With that in mind, I write about cogongrass control with some frequency. If you follow Panhandle Ag e-Newsand/or Panhandle Outdoors you’ve probably seen much of what’s included below before. That’s ok, a refresher never hurt anyone and, unfortunately, there are plenty of folks out there who are just realizing that they have a cogongrass problem.
It has been my observation that the difficulty of management and the corresponding limited early success often led to frustration and ultimately a loss of interest in control efforts on the part of landowners/managers. This is the absolute worst-case scenario, as diligence over time is paramount to successfully managing cogongrass. With all this in mind, optimizing the impact of the initial control effort is crucial both in terms of biology (efficacy on the plants) and psychology (keeping the landowner encouraged and motivated). If you have cogongrass to fight, take every step you can to get the absolute best results out of every treatment, especially the first one.
Cogongrass has no visible jointing, segmentation, or branching above ground. However, in the top 3-6 of the soil it forms a dense mat of white, fleshy, clearly segmented rhizomes which are a key identifying feature. Photo Credit: Mark Mauldin
The following is a discussion of some of the steps you can take to maximize the efficacy of your control efforts.
1) Timing Matters
Cogongrass is best treated with a fall-spring, one-two punch. Mid-summer and mid-winter treatments are not advisable. Based on my experience, the ideal time to treat cogongrass is October through November, before first frost, with good soil moisture. Spray now, during the fall window, and be prepared to spray again in the spring when you have at least 12 inches of green leaf and good soil moisture. I have mentioned “good soil moisture” twice… what exactly does that mean? It means there is sufficient moisture in the soil that the cogongrass is not experiencing any level of drought stress. Herbicide applications made to stressed plant are generally less effective than are applications to made to “happy plants”. It is very hard to see symptoms of drought stress in cogongrass. Generally, you need to look at the plants around the infestation for clues. If any of the plants in the surrounding landscape look wilted or crispy during the heat of the day, it’s probably best to delay herbicide applications. This concept is worth noting primarily because here in the central panhandle we tend to be dry during both the fall and spring application windows. I am writing this article on 10/9/24. At my house we’ve not had a drop of rain since Hurricane Helene came through on 9/27 and my trusty weather app say not to expect any for the next 10 days. While it will vary greatly by location and soil type, it loos to me like we are running out of hurricane moisture, and it is rapidly becoming too dry to spray. All this boils down to the fact that you need to be ready take advantage of the situation and spray when soil moisture is adequate.
With that one-two punch successfully delivered, you should see significant reduction in the size of the infestation by this time next year. Keep repeating the fall-spring process until you can no longer find any cogongrass. Be sure to look carefully, as the infestation retreats it can be easy to miss the less robust and more scattered remnants mixed in with other vegetation. These remnants need to be sprayed, if not rapid regrowth will occur.
Close examination of this cogongrass patch shows regrowth occurring in the patch and growth that was apparently missed by the prior herbicide application. Both of these scenarios are common and help to illustrate why it is important to scout diligently and be prepared for re-treatments. Photo credit: Mark Mauldin
2) Coverage & Leaf Area are Crucial
To make the most out of each treatment you must maximize the amount of chemical you get into the plant. This is done by getting thorough coverage on as much green leaf area as possible. Make sure you have plenty of green leaves (at least 12inches) and spray them like you’re painting a wall. You don’t want runoff, but you want every square inch of leaf covered with spray. Don’t mow or burn for at least 30 days after you spray. Cogongrass can be hard to spot when it is growing mixed with other grasses/green foliage. Look diligently to find the edge of the patch and then spray 10ft past the known edge on all sides of the patch.
3) Get the Spray Mixture Right
Notice, I didn’t say pick the right chemical. There’s more to it than that. The following recommendations will be based on managing cogongrass with the active ingredient glyphosate. (Imazapyr is also very effective on cogongrass, but due to its soil activity it is inherently more complicated to use and ensure the safety of desirable plants near the treatment area. I am not comfortable recommending imazapyr without first seeing the site where it is to be applied and discussing the risk to other vegetation with the landowner. Glyphosate must enter a plant through a green leaf making it much easier for applicators to ensure the safety of desirable vegetation.)
Generally speaking, the efficacy of glyphosate will increase if a water conditioner and surfactant are included in the spray solution. To clarify, this means there would be three separate products going into the spray tank – one herbicide and two adjuvants. The preferred water conditioner would be a 34% liquid Ammonium Sulfate (AMS) product and the surfactant would be an 80/20 Non-ionic surfactant (NIS). These products should be available anywhere ag chemicals are sold (not the garden center at a big box store) under many different name brands. Selecting a glyphosate product can be somewhat confusing, simply because there are so many different products on the market. The product amounts listed below are based on a 41%, 3lbs acid equivalent (ae) per gallon glyphosate product. This is a relatively common formulation, but there are many others available. All can be effective; it is just a matter of value and correctly adjusting the rate to match the formulation you are using.
For a broadcast application using a tractor mounted sprayer or other similar equipment, mix a spray solution such that 1 gallon of 41%, 3lbae glyphosate herbicide is applied per acre. Ideally this would be delivered in 10-20 gallons of water (be sure spray equipment is properly calibrated). Add a liquid AMS water conditioning product at 2% v/v before adding herbicide to the tank. Add a non-ionic surfactant (80/20 NIS) at 1qt per 50-100 gallons of spray solution after the herbicide has been added.
I understand that nobody likes to have to deal with all the numbers, especially the various formulations of glyphosate. Unfortunately, that’s just part of it… There are so many different products out there that the numbers are necessary to communicate the recommendations in a way that is widely applicable. Please don’t hesitate to contact me (850-638-6180) or your local UF/IFAS Extension Agent for assistance sourcing vegetation management products or tailoring the recommendations to match the specific products you have on hand. The most important thing is to get the mixture right and make the application be as effective as possible.
More than any other weed I manage, Cogongrass penalizes the applicator for not paying attention to the details. It is a very difficult plant to control; partial efforts are essentially a waste of time. I encourage you to take the extra time, effort, and expense and make the most of every application.
Lionfish first appeared in the northern Gulf of Mexico in 2010. At that time, it was a huge concern – and still is – but it got the public’s attention. Fishermen were concerned that lionfish would deplete targeted species they enjoyed catching and made money from. The number of lionfish divers were encountering was staggering and videos showed reefs that were basically covered with them, and few other species around.
The Invasive Lionfish
The community reacted by initiating a few local tournaments with awards and prizes and there was a push to harvest them commercially as a food product – lionfish are very good to eat. In 2013 the Florida Fish and Wildlife Conservation Commission and Florida Sea Grant held its first regional workshop to discuss the state of the lionfish invasion in our area and how management efforts were going. It was reported at the time that lionfish densities off the Pensacola area were among the highest in the South Atlantic region. They seemed to have a preference for artificial reefs over natural ones and there were studies suggesting how frequently lionfish removal efforts were needed in order to decrease their population. Studies showed that on reefs where lionfish were abundant, red snapper stayed farther away and further up in the water column. There were several talks on the general biology of the creature – which was still unknown to much of the public.
The Lionfish Removal and Awareness Day Event in 2017. Photo: Rick O’Connor
In 2019 the 2nd regional workshop occurred. The densities of lionfish had declined – possibly due to the commercial and recreational harvest efforts as well as the lionfish tournaments that were occurring. It was at this time that divers began to notice skin lesions on some of the fish and there were questions as to what was causing this and whether it had an impact on their populations. The commercial harvesting had not gone as well as expected primarily due to pricing issues, but education/outreach efforts had made a big impact – almost everyone knew about lionfish and the problems they were causing. Some on the commercial harvest side of the issue had turned to taking visiting divers out to hunt lionfish. For many this was a more lucrative venture than harvest and selling. But people still wanted to eat lionfish and finding local places that served was not easy.
Skin ulcers have been found on many lionfish in the region. Photo: Alex Fogg
The 3rd Regional Lionfish Workshop was scheduled for 2024 and occurred in February in Ft. Walton Beach. 52 attended to hear presentations on the latest research, commercial harvest, tournaments, and education/outreach efforts. Here are some highlights from those presentations.
Research Updates
The high densities in 2013 had declined by 2019 but there was no update on current densities of lionfish. Anecdotal evidence from divers suggested that they may be increasing again.
The source of the skin lesions was still unknown, but some evidence suggested that it could have contributed to the decline of lionfish between 2013-2019. The lesions are still occurring in lionfish.
eDNA studies by the University of West Florida found lionfish eDNA in samples collected from the upper portions of local estuaries – suggesting they may have entered the bay. The research team also found lionfish eDNA in the feces of some shorebirds nesting in the area. This triggered more questions than answers.
PCB monitoring in fish tissue obtained from the USS Oriskany as part of the artificial reef permit. The initial target species for this study have declined on the wreck – or at least at not as frequently harvested as the study required. However, lionfish have increased on the reef and are now being used to continue this monitoring project.
Commercial Harvest Updates
Florida Sea Grant presented results of a regional survey of seafood buyers and restaurants. Few were selling lionfish. Concerns included size and yield from processing, adequate supply, and the fact they were venomous. However, almost all of them were interested in selling lionfish and were willing to learn how to navigate these barriers to make it happen.
Tournament Updates
The FWC Lionfish Challenge is still going strong, and they plan to continue to support it.
The Emerald Coast Open is still the largest lionfish tournament in the country. This year they harvested over 18,000 lionfish.
Overall, across the region and state, lionfish tournaments were on the decline.
International tournaments reported mixed results – some doing well, some not so well. Those doing well were doing very well.
A new tournament was kicking off in Pensacola during the fall season – the Pensacola Lionfish Shootout.
Education and Outreach Updates
Citizen science programs are increasing.
Many school programs have included lionfish topics within their lesson plans.
Some questions remain unanswered currently.
Have the densities of lionfish increased or decreased since 2019?
What is the cause of the skin lesions found on some lionfish?
Are lionfish inhabiting parts of our estuaries?
Can we get lionfish on more menus in the region?
The next regional workshop is scheduled for 2029. Until then, many will be involved in trying to answer these questions and manage this problem. If you have any questions concerning the current state of lionfish in our area, please contact your county extension office.
Cogongrass (Imperata cylindrica) is one of the most noxious weeds in the U.S. and has been a problem in the agricultural and timberland for decades. In more recent years it has been found on our barrier islands. Stands of cogongrass on the beaches are not as massive and dense as they are in the upland regions of our district, but now is the time to try and manage it before it does. And NOW is the time to identify whether you have it on your property or not – it is in seed.
Cogongrass shown here with seedheads – more typically seen in the spring. If you suspect you have cogongrass in or around your food plots please consult your UF/IFAS Extension Agent how control options. Photo credit: Mark Mauldin
Cogongrass produces blades that resemble St. Augustine but are taller and wider. The blades can reach a height of three feet and the color is more of a yellow green (lime green) than the deep green of St. Augustine. If you can touch the blade, you will notice that the midline of the parallel leaf veins is off center slightly and the edges of the blades are serrated – feeling like a saw blade when you run fingers from top to bottom. They usually form dense stands – with a clumping appearance and, as mentioned, it is currently in seed, and this is very helpful with identification.
The midline vein of cogongrass is off-center. Photo: UF IFAS
The seeds are white, fluffy and elongated extending above the plant so the wind can catch them – similar to dandelions. These can easily be seen from the highway or riding your bike through the neighborhoods. As mentioned above, if you see seeds like this you can confirm the identification by examining the leaf blades. You can also send photos to your county extension office.
The white tufted seeds of cogongrass. Photo: University of Georgia
If the identification is confirmed the next step is to report the location on EDDMapS – https://www.eddmaps.org. You can also do this with the free app IveGotOne (which can be found on the EDDMapS website or any app store). HOWEVER, you cannot report private property without their permission.
The next step would be management. It is not recommended to mow or disturb the plant while in seed. Herbicide treatment is most effective in the fall. Many will mow the plant, allow the grass to resprout no more than 12 inches, and treat this with an herbicide. It is recommended that you contact your county extension office for recommendations as to which herbicide to use and how.
The negative impacts of this noxious grass have been an issue in the upland communities for decades. There have been few major issues with it in the coastal zone, but early detection rapid response is the most effective management plan to keep negative impacts from occurring. We encourage coastal communities to survey for cogongrass while it is in seed and develop a management plan for the fall.
Organized and sponsored by Florida Sea Grant, the “Stem to Stern” workshop in November 2023 at the Emerald Coast Convention Center marked a significant gathering in marine conservation and management. This event drew together legal experts, representatives from the Florida Fish and Wildlife Conservation Commission (FWC), local marine resource coordinators, law enforcement, and industry stakeholders to tackle critical issues facing Florida’s marine environments. Through discussions that ranged from legal frameworks for boating and waterway access to environmental conservation strategies, the workshop facilitated a deep dive into the complexities of marine policy and stewardship. Discover new programs, insights, and collective expertise shared at “Stem to Stern.”
Florida Sea Grant Boating and Waterways Workshop
November 2, 2023 Emerald Coast Convention Center
1250 Miracle Strip Parkway SE – Ft. Walton Beach FL
9:00 – 9:25 WELCOME AND INTRODUCTIONS
Welcome
Rick O’Connor (Florida Sea Grant UF IFAS Extension)
Moderators –Mike Norberg and Jessica Valek (Okaloosa County)
3:15 – 3:45 WRAP UP – Robert Turpin (Escambia County Marine Resources)
PROGRAM SPONSORS
Acknowledgement
We extend our deepest gratitude to all who contributed to the success of the “Stem to Stern” workshop. To our esteemed speakers, whose expertise and insights into marine conservation and management have been invaluable, we offer our sincere thanks. Your presentations were not only informative but also inspirational, guiding us toward a more sustainable future for our waterways.
A special acknowledgment goes to the members of the planning and program committee. Your dedication and hard work in organizing this event did not go unnoticed. From the initial planning stages to the execution of the workshop, your efforts have been the backbone of this successful gathering.
We also want to thank the authors of the surveys that have provided us with essential data and perspectives. Your research and analysis contribute significantly to our understanding of the challenges and opportunities within Florida boating and waterways.
Lastly, we are incredibly grateful for the support from our sponsors. Your generosity and commitment to Florida Sea Grant and marine conservation have been crucial in bringing this workshop to life. Your support not only made this event possible but also highlights your dedication to safeguarding our marine ecosystems.
Together, we have taken an important step towards protecting and enhancing Florida’s waterways. Thank you for your contributions, commitment, and shared vision for a sustainable future.
Information edited and compiled by: L. Scott Jackson, Chantille Weber, and Amon Philyaw, UF/IFAS Extension Bay County
An Equal Opportunity Institution. UF/IFAS Extension, University of Florida, Institute of Food and Agricultural Sciences, Andra Johnson, Dean. Single copies of UF/IFAS Extension publications (excluding 4-H and youth publications) are available free to Florida residents from county UF/IFAS Extension offices.
With our articles this week we hoped to make you more aware of what an invasive species is, why they need to be managed, and some of the threats that exist in the Florida panhandle. We highlighted several species but there are many more. Some, like Chinese Tallow and Japanese Climbing Fern, are well established and will never be eradicated. Others, like giant salvinia and the Cuban treefrog, have been detected early enough that there MAY be a chance. As with all of these species – we only know what we know. It is likely that all locations of these species have not been reported.
This is where you can help.
Volunteers from the University of West Florida are removing beach vitex from Pensacola Beach.
Photo: Rick O’Connor
The first thing you can do is become familiar with the invasive species in your area.
The Six Rivers Cooperative Invasive Species Management Area (CISMA) includes Escambia, Santa Rosa, Okaloosa, Walton, Homes, and Washington counties in the Florida panhandle. It also includes Baldwin, Escambia, and Covington counties in Alabama. On their website you will find a tab on the tool bar labeled EDRR. Here you can see a list of EDRR species found for this CISMA. We also have a list of what we call the “Dirty Dozen”. These are the top 12 established invasive species in this management area. The Apalachicola Regional Stewardship Alliance CISMA includes Bay, Calhoun, Franklin, Gadsden, Gulf, Jackson, Leon, Liberty, and Wakulla counties. You can find the same information for that area at theirwebsite.
Second, report any invasive species to the EDDMapS database.
This is a national database used by resource managers to assess the status of invasive species in their area and develop management plans to address. We need your help reporting. You can do so on that website or download the app I’veGotOne from the website or your favorite app store. This is a free app that will allow you to photograph and report invasive species from the field. The data from this app populates the EDDMapS database.
Third, help manage these species.
You can do this on your property or participate in a community event that is removing invasive species in your area. If you have questions on the best methods for managing your property, or where a local event is occurring, contact your county extension office or your local CISMA.
Fourth, help us educate more in the panhandle about this issue. The effort to manage invasive species is similar to managing litter and debris. The more groups that are engaged, the larger our impact will be.
ARE YOU AWARE THAT GIANT SALVINIA HAS BEEN FOUND IN THE FLORIDA PANHANDLE?
Most likely not.
The number of reports in the entire of Florida are very few. So, unless you live near one of the infested areas you are most likely not aware of this invasive plant.
This is an EDRR species with reason for concern.
The first record of this plant in the Pensacola area was in 2018. I was called to a local residence to discuss a possible living shoreline when we observed giant salvinia (Salvinia molesta) floating on the west arm of Bayou Chico. Further investigation found the plant inhabiting the north arm of Bayou Chico as well as the Jackson Lake area. Though not reported on EDDMapS, we now know the plant has moved into the retention pond at nearby Lexington Terrace. There are currently nine records of this plant in that area, but we know that the plant covers much of that waterbody.
Active growing Giant Salvinia was observed growing out of the pond water on to moist soils and emerging cypress and tupelo tree trunks. Photo by L. Scott Jackson
At that time, I checked EDDMapS for other records in Florida. There was a report from Bay and one from Gadsden Counties. I did note that there were large infestations in Louisiana and Texas. There were also posts and videos from Texas explaining the bad situation they had and how residents there could help. The concern was so high from those states that the Florida Fish and Wildlife Conservation Commission formed a small team, based out of Bay County, to battle this plant and reduce its chance of spreading here. A true EDRR effort. That team is very present in Escambia County with constant survey and treatment projects ongoing.
A couple of years ago I was heading out west to camp. Our first stop was at Lake Bistineau near Shreveport LA. After setting up camp we walked down to the lake and witnessed a lake completely covered with small floating plants. No water could be seen. I did see a floating screen holding the floating plant outside of the swimming area. We walked onto a dock set up for fishing but there was no way you could fish there. The plant was so thick it would be impossible to get your bait below the surface. Then it hit me… this was giant salvinia – the plant FWC and local counties were working on controlling. I could see firsthand what would happen if we did nothing. From the dock I walked over to the swimming area and found a sign informing everyone about the potential threat of this plant and to be very careful NOT to take it with you to another area of the lake, or another body of water. After returning home, I worked with our county to educate the public about this plant, how to identify, report, and manage it.
Giant salvinia overgrowth in a backwater section of Bayou Chico in Escambia County. Photo credit: Escambia County Natural Resource Management
Giant salvinia is originally from Brazil and Argentina. It resembles our native duckweed but the leaves are larger – 0.5-1.0 inches long. It was intentionally brought here as an aquatic ornamental plant. It prefers freshwater with little or no movement and high in nutrients. We already mentioned how it can impede fishing and swimming – but it also blocks sunlight needed for submerged grasses and, during decomposition, can lower the dissolved oxygen within the water to levels lethal to fish and invertebrates.
The nine records in Pensacola, one in Panama City, and one in near Quincy have now been joined by 12 other records in Florida. Nine are in Jacksonville, two near Naples, and one near Lakeland. It has also been reported in South Carolina, Georgia, Alabama, Mississippi, Louisiana, Texas, and the California/Arizona state line.
This is not a plant we want to spread across our state, EDRR is very important here.
What can you do to help?
Report any possible sighting to your local county extension office. If you are not sure if it is the plant – report anyway, someone will come out to verify the identification.
If it is small patches, remove from the water using a crab net, or swimming pool skimmer, place the plant out in the yard in direct sunlight to dry and kill it. It can then be double bagged and thrown in the trash.
If there are large areas covered with the plant, again, contact your county extension office who will connect with the FWC team to begin treatments.
As always, if you have any questions about this, or any other invasive species, contact your county extension office.
