Broad-Leaved Panic Grass, Broadleaf Rosette Grass
Synonyms of Dichanthelium latifolium: Milium latifolium (L.) Moench, Panicum latifolium L., Panicum macrocarpon Leconte, Panicum macrocarpum Leconte ex Torr., Panicum schneckii Ashe
Dichanthelium latifolium (L.) Harvill is the correct and accepted scientific name for this plant. It was named and described as such by Alton McCaleb Harvill, Jr. in Castanea 1977. It was first named and described as Panicum latifolium by Carl von Linnaeus in the first volume of the first edition of Species Plantarum in 1753.
The genus, Dichanthelium (Hitchc. & Chase) Gould, was named and described as such by Frank Walton Gould in Brittonia in 1974. It was previously cited as subgenus Panicum subgen. Dichanthelium by Albert Spear Hitchcock and Mary Agnes Chase in 1910.
Plants of the World Online lists 93 accepted species in the Dichanthelium genus (as of when I am updating this page on 2-12-20). The genus is a member of the Poaceae Family along with 748 other genera. Those numbers could change.
The above distribution map for Dichanthelium latifolium is from Plants of the World Online. Ares in green is where the species is native and purple where it has been introduced (Republic of the Union of Myanmar). The distribution map on the USDA Plants Database is the same for North America.
There are several links at the bottom of the page fr further reading and better ID information.
There is a swampy area in the southeast corner of my farm in Windsor, Missouri where this species has run rampant. When I first moved back here to the family farm in 2013, the Impatiens capensis (Jewel Weed) was king of the swamp. Not any more… The area is a swamp partly because the Farrington Park Lake has a drain in the area. To give a little more history, which may not matter to you, the Rock Island Railroad used to run along the south boundary of the farm. The railroad uses soil along where they need to buildup the “road bed” for the tracks which is what partly happened with the southeast corner of the farm. Back in the steam locomotive days, Rock Island Railroad dug a lake on the other side of the tracks for water for the steam locomotives. One steam was replaced by diesel engines, the railroad donated the lake and surrounding land to the city of Windsor for a park. The Rock Island Railroad is now part of the Katy Trail. Anyway, there is a drain under the trail that drains in a low spot that was dug by the railroad to buildup the tracks. This corner of the farm is low anyway and there is always water standing between the fence and trail right-of-way. Despite it being a mosquito haven and Japanese Honeysuckle have taken over the fences, there is also an abundant amount of other insects and birds. I have been there in the past and there were MANY Hummingbirds.
The first and second photos were taken on July 25 (2019) and it took a while to figure out what in the heck it was. At that stage, or any other for that matter, you wouldn’t think it was a type of grass. I thought it could be a species Tradescantia (Spiderwort) or maybe a species of Persicaria (Smartweed/Knotweed). The leaves didn’t actually match any species of either two and there were no flowers to look up. Finally, I sent photos to a horticulturalist who maintains the Midwest Weeds and Wildflowers website from Mississippi State University (Springfield, MO). Although she doesn’t have them on her site, she told me they were Dichanthelium latifolium. I looked them up online and she was correct.
Over the next several months I took a lot of photos of this colony that wasn’t in the swamp. They had escaped the swamp and a fairly good-sized colony was growing next to the fence along the back of the pasture.
There isn’t much online about this species which was another reason I had some difficulty. One of the best ways to figure out what species of wildflower you have is with their flowers. But, with this one there were no flowers.
Dichanthelium latifolium is a clump-forming perennial grass with short (or no) rhizomes. Stems grow from 1-4 feet long, sort of erect at first but tend to sprawl as they grow taller. The genus was formerly a subgenus of Panicum but became a separate genus in 1974.
At first, their leaves were fairly broad but they grow longer as the stems get taller and the season progresses. One characteristic feature of their leaves is their veins that run parallel to the midrib instead of from the midrib to the margin.
The base of the leaves are clasping, meaning they clasp around the stems.
Every day when I went to the back of the farm I looked for flowers. All I was seeing was what looked like remnants… Steyermark’s Flora of Missouri says their inflorescences are 6-15 cm long… Hmmm… That’s around 2 1/3 to about 6 inches.
Steyermark’s further states earlier inflorescences are larger than the later ones and are loosely ascending to spreading, mostly “rebranched”. I think that means they form secondary branches… Hmmm… So, does that mean the inflorescence forms secondary branches? The description is sort of complicated and talks about spikelets and glumes… 🙂 I would just write what Steyermark’s says, but that might break some kind of copyright rules.
The dictionary on my computer says a glume is “each of two membranous bracts surrounding the spikelet of a grass (forming the husk of a cereal grain) or one surrounding the florets of a sedge.”
A spikelet is “the basic unit of a grass flower, consisting of two glumes or outer bracts at the base and one or more florets above.”
One word seems to lead to another, so I think I better stop while I think I am ahead.
Inflorescence, glume, spikelets… at the top of the stem poking through a clasping leaf.
I uploaded photos on iNaturalist as an observation for Dichanthelium latifolium and a member asked if I was sure it wasn’t D. clandestinum. Until I started using iNaturalistI always pretty much used Missouri Plants for ID. They have no Dichanthelium species listed so I had no clue… Then, I checked out Steyermark’s Flora of Missouri which was still confusing. Then, I went to the Illinois Wildflowers page and read about D. clandestinum and then the muddy water cleared somewhat.
Supposedly, they produce an “exerted” inflorescence earlier in the season and another set, after the stems branch out, with inflorescences that are partially hidden. That must be what I am seeing in these photos that were taken on September 1st…
I noticed some of the leaves have jagged margins.
The upper stems and definitely “pubescent” (hairy) while not so much at the lower portion of the plant.
Here’s an idea of how long the stems can get. They can also root at the lower leaf nodes.
Sometimes I take photos for a reason then later don’t remember why… Well, I am writing this page 9 months after I took the photos. I catch up on updating the blog and writing new pages over the winter.
I will take more photos in 2020 and maybe I can photograph better flowers, glumes, spikelets, or whatever you want to call them.
I have enjoyed photographing and learning about the many wildflowers growing on the farm and other areas. I have grown over 500 different plants and most have pages listed on the right side of the blog. I am not an expert, botanist, or horticulturalist. I just like growing, photographing and writing about my experience. I rely on several websites for ID and a horticulturalist I contact if I cannot figure them out. Wildflowers can be somewhat variable from location to location, so sometimes it gets a bit confusing. If you see I have made an error, please let me know so I can correct what I have written.
I hope you found this page useful and be sure to check the links below for more information. They were written by experts and provide much more information. If you can, I would appreciate it if you would click on the “Like” below and leave a comment. It helps us bloggers stay motivated. You can also send an email to me at firstname.lastname@example.org. I would enjoy hearing from you.
*World Flora Online is not up to snuff on this species yet and say Dichanthelium latifolium is a synonym of Panicum latifolium. They will be uploading from Plants of the World Online soon so they will be in agreement. They are a work in progress…