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The grass is not always greener on the other side. Cogongrass is a good example of how non-native plants can take over the landscape, disrupt our fragile ecosystem and take years to eradicate. This is one more reason why we should plant native alternatives instead.
Imperata cylindrica, also known as cogongrass, is highly invasive in the Southeastern U.S. It spreads across the land at a rate exceeding that of the kudzu vine, Pueraria lobata. In fact, I. cylindrica has eclipsed the kudzu vine as the most obnoxious weed in the state of Florida.[1] It is listed as a federal noxious weed in the United States. If you think you have cogongrass on your property, please contact your state department of agriculture or USDA-APHIS office.
Dr. Shibu Jose is an associate professor of forest ecology in the School of Forest Resources and Conservation at the University of Florida. He has done extensive research for a decade into the growth habit, spread and management of this non-native invasive plant. In 2003, the estimated number of acres which contain or are covered by kudzu in the Southeast was 1 million while cogongrass covered 1.5 million acres. Florida alone was estimated to have about .5 million acres of the grass.[2]
Wilson Faircloth, USDA Agr. Research Serv., Bugwood.org
Cogongrass first arrived in the U.S. by ship from Japan in Mobile, Alabama in 1912. At that time, it was being used as packing material. Much like the kudzu vine, cogongrass was then deliberately planted by well-meaning Americans. In the 1920s ranchers planted it with the hope that they had found a new forage crop for their cattle. Cattle ate the grass when it was very young but would not eat it once it was mature. This was thought to be due to the sharp edges on the leaves, caused by silica, once the plant matured.
The Department of Transportation in several states planted the grass along highways in an attempt to control erosion. Like the kudzu vine, this caused more harm than good.
Japanese Blood Grass Photo courtesy of Dave's Garden member, hczone6
The grass is a perennial. It forms rhizomes that spread very aggressively. The rhizomes have barbs that can actually penetrate roots of surrounding plants. This grass not only competes for food and water, it wins. When cogongrass is present, native species die out. Native tree seedlings and grasses are pushed out disrupting the entire ecosystem of the area. Wildlife dependant on native species can no longer survive where cogongrass has taken over.
Cogongrass tends to grow in thick circular patches. The leaves are yellow-green, three to four feet long and may reach six feet long although, this is not typical. Flower/seed heads are cylindrical and up to eight inches long with fluffy white seeds that can be easily carried on the breeze.
Managing Cogongrass
When treating cogongrass, you should make certain to cover entire plant with herbicide. You will need to spray plants as soon as they emerge and not wait for them to mature, if possible. If plants are treated during a drought, they will most likely survive the herbicide and need retreatment.
"Cogongrass in small (less than 20-foot diameter) patches can be treated with a glyphosate solution in early fall (August to October)." Retreatment may be necessary. For more information on treatment and mixing instructions see "Wanted Dead Not Alive: Cogongrass" published by Auburn University.
Dr. Jose states that using fire only seems to help the grass thrive in that it kills off other plants growing nearby, giving cogongrass more space to spread. Burning may be used in conjunction with other treatments to eradicate the grass. He also subscribes to a regimen of herbicide application, mowing, tilling, burning and re-introducing native plants to an area invaded by cogongrass.
Japanese Blood Grass Photo courtesy of Dave's Garden member, tomuck
Landscaping with Japanese Blood Grass
Several red-leaved forms of I. cylindrica have been cultivated for landscaping in the U.S. and is commonly known as Japanese blood grass. I. cylindrica 'Rubra' or ‘Red Baron' are still being sold and passed from gardener to gardener as one of the most common ornamental grasses planted in home gardens. Admittedly, it is a beautiful addition to the landscape; however, this plant can revert back to its green parentage.
In doing so, it may be considered part of the problem. This should be reason enough to search for other options for the home garden.
Japanese Blood Grass Photo courtesy of Dave's Garden member, mgarr
There aremany choices that rival Japanese blood grass. Why not try the North American native Schizachyrium scoparium, little bluestem, for its blue-green stems which turn a nice bronze-purple in the fall? This grass flowers in pairs followed by seeds that look like silvery-white feathers which mature in the fall. S. scoparium 'Blaze' matures later than little bluestem and has very vivid fall color.
Also a native, the very showy Muhlenbergia capillaris orGulf muhlygrass, puts on a show to beat the band. It will fill an area with a lovely purple haze of feathery blooms that will have all the neighbors talking about your garden. The flowers appear in late summer and are replaced by seeds that are just as showy.
Another native is Sorghastrum nutans or indiangrass. This grass has graceful light green to blue leaves with yellow-gold blooms in summer followed by golden foliage in the fall.
There are many grasses that will fit perfectly in the home landscape. Doing a bit of research before you plant is always a good idea.
Happy Gardening
Top right photo used with permission, John D. Byrd, Mississippi State University, Bugwood.org
Shibu Jose, Assistant Professor, School of Forest Resources and Conservation, University of Florida, 5988 Highway 90, Building 4900, Milton, FL, 32583
"Alien Plant Invasions: The Story of Cogongrass in Southeastern Forests" published by Society of American Foresters and co-authored by Dr. Shibu Jose is a good source of information on cogongrass.
Dr. Richard "Rick" Williams, Associate Professor, Extension Forestry Specialist, School of Forest Resources and Conservation, University of Florida, 5988 Highway 90, Building 4900, Milton, FL, 32583
About Jacqueline Cross
I'm a native Floridian...feet planted in the shifting sands of northwest FL. but my heart strings are tightly knotted to the hills of Tennessee.
I live my poodle, Minnie Pearl, Zsa Zsa the cat who runs the whole show and a new addition, Kitty Belle.
I'm a writer, gardener, quilter, cross stitcher, soapmaker and nature lover. Mother to 3 wonderful daughters & Nana to 6 perfect grandchildren.
I also write for Suite101 and was promoted to Feature Writer in the vegetable gardens section in 2008.
Posted by wandygirl (from Brookfield, CT) on November 18, 2008 at 6:38 PM:
Your article reminds me of a discussion that came up in an ecoIogy class I took a few years ago. I have had 'Red Baron' in my zone 6 Connecticut garden for about 7 years. So far it has not shown signs of reverting. If anything it is considered to be a fussy plant around here. With the way people travel these days it is not unreasonable to envision a seed from a plant in CT traveling on someone's clothes or belongings taking root in Florida and adding to the problem. Even so, I'm not ready to say that a plant that is invasive in one region should be banned in the entire country. There are folks in the invasive plant community who are advocating nationwide bans on plants that are only invasive locally. It is worthwhile to discuss whether this should be done, but I don't think the general horticultural community is ready for such a measure.
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Posted by libellule (from Fountain, FL) on November 18, 2008 at 8:57 PM:
Wandygirl,
It does seem extreme to ban a single plant because it is invasive in only a few areas or one region. However, plants adapt to different situations over time and may very well become invasive in other areas. It is hard to predict what might happen down the road.
I live in an area where everything seems to get out of control and this is why I am an advocate for native/non-invasive plantings of all kinds.
That said, I really do like the red grass!
JC
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Subject: Thank You
Posted by Kelli (from Los Angeles (Canoga , CA) on November 12, 2008 at 4:45 PM:
I have thought of getting some Japanese blood grass. Now I know not to. The last thing I need is another invasive grass in my yard.
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Posted by libellule (from Fountain, FL) on November 12, 2008 at 11:47 PM:
Kelli,
I just love the look of these grasses but too afraid of anything that chokes out the natives.
They are sort of like the lion in sheeps clothing :-(
J
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Subject: Good
Posted by phicks (from Lakeland, FL) on November 12, 2008 at 11:10 AM:
Good Article and Pictures Paul
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Posted by libellule (from Fountain, FL) on November 12, 2008 at 12:16 PM:
Thanks, Paul.
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Posted by pajaritomt (from Los Alamos, NM) on November 12, 2008 at 1:50 PM:
Thanks for the heads up on this invasive grass and the variety that can be used in landscaping and which probably shouldn't be. I was unaware of this problem.
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Posted by joegee (from Bucyrus, OH) on November 12, 2008 at 2:26 PM:
I purchased blood grass a few years ago. I will be destroying it in the spring.
Thank you for the informative article.
-Joe
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Posted by Sharran (from Calvert City, KY) on November 12, 2008 at 4:44 PM:
Nice article, you always make me want to be further south!
Thanks.
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Posted by mellielong (from Lutz, FL) on November 12, 2008 at 7:58 PM:
I volunteer with the invasive species task force in my county. It is such a joy to change a plot of land from being infested by invasives back to its native state. I started with a small part of my backyard that was under the power line supports (and a prime target for birds pooping out seeds). It's now my bromeliad garden! I've also been eradicating the invasive Cuban Tree frog and I've noticed more native (green) anoles than ever and I've even seen a few regular native green tree frogs! When I started branching out into the neighbors' yards, Dad suggested I try to find something where I could work at clearing invasives from land where people welcomed me. Thus, my volunteer work!
I always prefer natives because as a gardener, they are much easier to care for. Especially when you live in a crazy weather area like I do. Also, anyone interested in attracting wildlife (or butterfly caterpillars like I do!) should focus on using native plants that have evolved alongside the animals and insects of your region.
Thanks for bringing attention to this problem and educating gardeners. I must admit when I was a newbie gardener I made a few "mistakes" when choosing plants. Luckily, I've learned my lessons and fixed those mistakes!
Melanie
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Posted by Sharran (from Calvert City, KY) on November 12, 2008 at 8:56 PM:
Jackie,
Mellielong, you are a source of knowledge for me. Nice to see you here, too.
sharon
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Posted by mellielong (from Lutz, FL) on November 12, 2008 at 9:03 PM:
I'm all over the place! I was just commenting on the Tampa Tribune's site about why the controlled burn the parks department is doing is a good thing. All they ever get are complaints about the smoke so I was explaining why these burns are a good thing. My favorite ignorant comment of the day was the lady who said that Mother Nature sets these fires when they're supposed to happen, and that may be thousands of years from now. Yeah, Tampa is the lightning capital of this hemisphere! We should be on fire all summer! Darn those pesky firefighters for putting out all the fires, LOL!
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Posted by libellule (from Fountain, FL) on November 12, 2008 at 11:59 PM:
Pajaritomt...You are welcome :-)
I'm glad you got some use out of this article.
Joe...Hopefully, you'll find something you like equally as well to replace the bloodgrass. :-)
Sharon...Thanks :-) Funny you say that about being further south...I am always envious when I hear y'all talk about home (up your way). I'd trade the heat and humidity here for a nice cold winter with a little white stuff any time! Would just have to have a hothouse for some of the ornamentals and veggies.
Mellielong...You sound like my kind of gardener! You are working toward something that will make a big difference, especially if you can get others in your area to do the same. They'll tell their family and friends and then they will tell theirs....on and on. It'll be a movement ;-)
