Dwarf Japanese Knotweed is a hardy, herbaceous, rhizomatous perennial. In the late 1800's it was brought to North America and quickly escaped cultivation. Dwarf Japanese Knotweed (Fallopia japonica var. This plant is taking over the yard on one side of my house! )on the plantings in the ditches. compacta, commonly called Japanese knotweed is clumping perennial which spreads by rhizomes and is often grown as a ground cover. Child L, Wade M, 2000. Japanese knotweed — Polygonum X bohemicum) are able to produce fertile seeds. The fruits are similar to other Knotweeds. Weed Killer - Weed Control - Weeds - Weed - Identifying Weeds - Australian Swamp Stonecrop - Buddleia - Creeping Water Primrose - Dandelion - Devils Apple - Dwarf Knotweed - Floating Pennywort - Giant Hogweed - Giant Knotweed - Goldenrod - Himalayan Balsam - Horse Tail - Mares Tail - Hybrid Knotweed - Japanese Knotweed - Parrots Feather - Ragwort - Rhododendron - Rosebay Willowherb - Tree of Heaven - Water Fern. Rosebay Willowherb It reaches up to 40 inches in height. That area has minimal regrowth. compacta; a variable species of which former names have included: Polygonum pictum, Polygonum compactum and Polygonum reynoutria. As it died, I went after the roots. compacta, is smaller with pink flowers and is less common but has also been widely planted in Minnesota. Fallopia japonica var. Dwarf Japanese Knotweed, var. Flowers reside in dense upright panicles, growing to 6cm long, and are often pink in male-sterile individuals. The leaves vary in shape and are often in concave form. Thank you.Katy Chayka, Minnesota Wildflowers. Web design and content copyright © 2006-2020 MinnesotaWildflowers.info. Cynthia, if you must have these plants, keep them in pots and keep them indoors. I also sprayed the diluted mixture on new plants (less than 12" tall). Any suggestions? Japanese knotweed ( Fallopia japonica ) is a weed that spreads rapidly. Stems grow to 1 metre, reddish. Japanese Knotweed goes by both latin names Polygonum cuspidatum (more common in North America) and Fallopia japonica (more common in Europe), with the latter accepted by “Flora of North America” (FNA, our definitive reference). … Parrots Feather. Nationwide Japanese Knotweed removal specialists, call us now on 0330 363 9555 for free expert advice Dwarf Japanese knotweed - Fallopia japonica var. Dwarf Japanese Knotweed is a hardy, herbaceous, rhizomatous perennial. I'm interested in digging some roots. (Ramsey county and Roseville have been alerted, but private landowners in the area may want to know). google_ad_width = 728; Fallopia japonica var. This is kind of urgent, as I have a friend with reacurring Lymes, and needs this soon. I've been trying to remove. I'm puzzled actually. compacta are alpine variants of Fallopia japonica, introduced to the UK for garden use. Intensive mowing of tops or mowing in combination with herbicide applications (such as Arsenal®) can deplete this plant's energy reserves over time. Now I know what it is and have been trying to eradicate it. I am interested in getting anyone's plant to grow in a pot inside year round. Plans are to do more cut and douse. It's a slow process, but seems to work. Fallopia japonica var. The species described on this page is var. Map of native plant purveyors in the upper midwest, Photos courtesy Peter M. Dziuk, taken at locations across Minnesota. Stems grow to 1 metre, reddish. Japanese knotweed is the most common of four invasive knotweed taxa present in the UK (Japanese and Dwarf knotweeds being varieties of the same species): 1a Japanese knotweed (Reynoutria japonica var. Yes, Nicole, Japanese knotweed can crack foundations here as well. See Terms of Use and Privacy Policy. compacta; a variable species of which former names have included: Polygonum pictum, Polygonum compactum and Polygonum reynoutria. A hybrid between Japanese and Giant Knotweeds—Bohemian Knotweed (Fallopia × bohemica)—is also present in the state. Female flowers can produce small 3-angled black-brown fruit but seed production is rare, primarily spreading by rhizomes. There are numerous other venues with more information and authority than we can provide. We recommend control and removal wherever this plant is found. compacta can also hybridise with Fallopia sachalinensis to produce a strain of Fallopia x bohemica. It is widespread in the eastern US and is likely now present in all of the lower 48 states. ), Actually I'm in Amery, Wi. Digging of even small clumps is labor intensive and safe disposal of the rhizomes is problematic. I have spotted a patch growing under a powerline between a road and a bike trail in Lino Lakes, about a mile north of the Anoka/Ramsey County line. I ended up getting info from the horticulture dept. The Japanese knotweed, also known as the reynoutria japonica has defined raised nodes and hollow stems which give it a bamboo appearance. Flora of North America still lists it as Fallopia japonica, with Reynoutria japonica Houttuyn a synonym. These cultivars can also be invasive. Dwarf Knotweed,