Virginia Jumpseed, American Jumpseed, Virginia Knotweed, Woodland Knotweed
Synonyms: Antenoron racemosum Raf., Antenoron virginianum (L.) Roberty & Vautier, Antenoron virginianum var. glaberrimum (Fernald) H.Hara, Polygonum virginianum L., Polygonum virginianum var. glaberrimum (Fernald) Steyerm., Sunania virginiana (L.) H.Hara, Sunania virginiana var. glaberrima (Fernald) H.Hara, Sunania virginiana f. rubra (Moldenke) H.Hara, Tovara virginiana (L.) Raf., Tovara virginiana var. glaberrima Fernald, Tovara virginiana var. kachina Nieuwl., Tovara virginiana f. rubra Moldenke
Persicaria virginiana (L.) Gaertn. is the correct and accepted scientific name for this species of Persicaria. it was named and described as such by Joseph Gaertner in De Fructibus et Seminibus Plantarum 1790. It was first named Polygonum virginianum by Carl Linnaeus and described in the first edition of Species Plantarum in 1753.
The genus, Persicaria (L.) Mill., was named and described by Philip Miller in the fourth edition of Gardener’s Dictionary in 1754. According to Plants of the World Online by Kew, there are currently 129 accepted species in the genus Persicaria. (as of 10-8-19 when I am writing this page). Those numbers will probably change as POWO makes updates.
PLEASE check the links at the bottom of the page for further information. They were written by experts.
Persicaria virginiana is a native resident of approximately half of eastern North America.
Please check out the links at the bottom of the page. They will take you to websites that were written by experts.
My first experience with the Persicaria virginiana began in 2017. Not that they haven’t always been somewhere here on the farm, I just hadn’t noticed them. I had probably been whacking hem off with the trimmer. When this “different” plant came up next to the steps to the back porch I decided to let it remain so I could identify it. It turned out to be Persicaria virginiana commonly known as Virginia Jumpseed. It has a few other common names such as American Jumpseed, Virginia Knotweed, Woodland Knotweed, and maybe a few others I am not familiar with.
I started getting more into wildflower ID on the farm (mainly) in 2018 and 2019. I decided to ID all the different Persicaria species (seven) growing here on the farm and needed more photos for P. virginiana. While I was at the back of the farm I noticed a pretty good colony of them by the gate that goes to the back pasture. The problem is that they are growing among Poison Ivy so I zoomed in to get a few shots… Flowers are spaced fairly wide apart on an inflorescence that can be up to 16″ or so long.
The two most distinguishing features about Persicaria virginiana is their large ovate leaves and their curious flowers (especially when they start to fruit) on very long racemes. This is really quite an interesting species when you check it out.
According to Steyermark’s Flora of Missouri (Volume 3, pages 737-738), Persicaria virginiana is a perennial while most of the other species here are annual. It also says they do not root at their nodes. The plants seem to grow more upright on stouter stems (in my opinion), which would explain why they don’t root at their nodes (because they are not decumbent). As with the other species, they have an ocrea (sheath) surrounding the leaf nodes (joint). To me, they appear to be more above the node. I really need to have a closer look and take better photos so I can explain what I see. If you click on the link below for Missouri Plants, you will see a great photo of the ocrea. The ocrea is brownish with kind of wooly looking hairs (cilia), appearing like someone took a wire brush to it. The ocrea may dry out and fall off with age. Leaves are rather large and ovate, up to around 6″ long x 3″ wide, with appressed hairs on both surfaces or just the upperside. Stems are more or less glabrous below and oddly roughish with appressed hairs on the upper stems. Of course, you can’t see the hairs without magnification but they feel slightly rough. Nope, I didn’t wade the Poison Ivy to have a closer look. Leaves can have a reddish to purplish V-shaped, crescent-shaped, or triangular splotch on the upper surface. I didn’t notice this on any of the plants here but some photos online do show this feature.
On September 22 I noticed a very small Persicaria virginiana in a wooded area behind the pond at the back of the farm. I took LOTS of photos but they didn’t come out well. The light was weird but at least there is no Poison Ivy there.
So much different than the other Persicaria species here…
Still not a good shot of the ocrea!
I took A LOT of photos of the flowers and even with the magnifying glass they did not turn out well. I need MORE!
The Missouri Plants website (link below) has a good photo of their open flowers. The flowers form a “beak” when starting to fruit. One very interesting thing I read in Steyermark’s Flora of Missouri was how they disperse their seed. It says tension builds up at the joint of the fower as the fruit matures which acts as a spring to shoot the seed up to 12 feet away. Passing animals also trigger this action then the seed gets stuck in their fur. The small two-angled seed tapers to a hooked beak (maybe the tail in the above photo is part of the seed). Seed can be black or brown, shiny or dull… I need to get a photo of those seeds!
WAIT A MINUTE!!!!
I HIT THE
Once it stopped raining this afternoon, Thursday, October 10 at 3 PM depending on when you are reading this, I decided I would see if I could find a closer Persicaria virginiana so I could get better photos of the ocrea, seed, and maybe open flowers. There were no more around the back porch or AC but I didn’t especially want to go to the back of the farm to wade in the Poison Ivy. There was one area I hadn’t been in pretty much all summer north of the chicken house. This area is about 150′ x 150′ and is where my grandparent’s old peach orchard was. I measured in the early 1980’s so I know how big it is. 🙂 Last year I backed the mower (with the tractor) in all this jungle and cleaned it up a bit. Anyway, I walked to the northeast corner and almost s–t! (sorry, but it’s true!)! Here right before my eyes was a HUGE colony of Persicaria virginiana!!! After I thought there were just a few on the whole farm, there is a HUGE colony right in the backyard!
There were no open flowers but there were SEEDS GALORE! Remember I mentioned how the seeds shoot out? Well, it is really true! One plant I touched literally vibrated as the seeds shot out!
And we have fuzzy ocrea! There were so many plants to choose from and I took over 50 photos total. Well, some were not that good and after choosing the best I saved 11. The wind was not being all that cooperative either. I truly hit the JUMPSEED JACKPOT! 🙂
The only photos I had trouble were close-ups of the flowers. Seriously, folks, I was experimenting with not one magnifying glass, but two, one on top of the other. It works like a charm and is much better than just one but it still takes practice and patience. LOL! The problem is with zooming in, and with two magnifying glasses, you have to be very still. If not, the camera complains about vibration. Zooming in with one magnifying glass was tricky and sometimes the camera would shut off and say “lens error”. With two, I didn’t have to even zoom in that much and the camera never shut off. I think I could take photos of the hair on a gnat’s eyebrow now. (I would say butt, but I already said s–t earlier which could be deemed as inappropriate behavior).
In the above photo, you can really see the “hooked beak” of the fruit. There are two…
Here’s a good one of the ocrea on one plant. The ocrea can be light to dark brown, depending on the preference of the plant. You can clearly see how the ocrea becomes dry and starts to tear away. This photo was taken toward the upper part of the plant so I could get a shot of the appressed hairs on the stem as well.
I think half of the photos I took were of the seed. The seeds are fairly small but larger than the other species. When I was removing the outer part of the achene I had to be careful not to remove the ” hooked beak”. The seed itself doesn’t have a beak and is part of the entire “fruit”. Hmmm… Like many other plants seed are part of what is called an achene. An achene is a dry, one-seeded, indehiscent fruit. Indehiscent means the achene (pod or fruit) does not split open to release the seed when ripe. Sunflower and strawberry seeds are two examples…
Persicaria virginiana can have white, green, or pinkish flowers. They are sometimes used in woodland gardens and there are a few cultivars with red flowers and variegated leaves. There is a rare variant of this species in the south with thicker leaves.
I enjoyed photographing and identifying the seven species of Persicaria growing here on the farm. I wrote a post called Perplexing Persicaria with links to all their pages.
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.