Please help me identify this red and green bamboo like plant.

Please help me identify this red and green bamboo like plant.


This plant is currently growing in my back yard, and it grows about an inch in 2-3 days, and it spreads. Please help!!!

Thank you in advanced for any information.

 

This is Polygonum cuspidatum aka Japanese knotweed, terrible weed.

 

It is Fallopia japonica, Common name Japanese knotweed. A very invasive weed, which can grow through tarmac, concrete etc. Do not try digging it up, even weeny bits can grow. Spray it with a Glyphosate weed killer,keep repeating this, you will get rid of it -eventually!! Good luck.

 

Thank you very much!

 

This plant has many names and it is hard to tell which one is "correct"... may be Reynoutria japonica?
USDA site: Polygonum cuspidatum, there are no Fallopia and Reynoutria in Polygonaceae at all.
Wikipedia: Fallopia japonica, with Polyogonum cuspidatum and Reynoutria japonica as synonims.
Flora Europea (RBG Edinburgh): Reynoutria japonica, syn. P.cuspidatum -- http://rbg-web2.rbge.org.uk/cgi-bin...ynoutria&SPECIES_XREF=&TAXON_NAME_XREF=&RANK=
Anybody knows what is the officially accepted name now?

 

When the experts don't agree, you have to make a choice and list synonyms if you think you need to to be clear. If I had to label the plant for the garden, I would use Fallopia japonica, based on the reports from RHS, GRIN and Flora of N. America. I probably would spend more time looking on Google Scholar for recent reclassification articles before actually assigning a name to it though. I don't have that time and it is a plant that will never be accessioned here.

One thing I do agree with, get rid of it.

 

And in case you have not seen this thread:

http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=20369

 

Although internet posters repeatedly identify such plants as Japanese knotweed in Seattle at least hybrid Japanese knotweed is predominant:

Virtually all books covering plants of the Northwest describe and illustrate the hybrid under the name Japanese knotweed. But purebred Japanese knotweed is relatively rare and small; its hybrid is larger, since the other parent is giant knotweed

--Jacobson, Wild Plants of Seattle - Second Edition

So far your plant appears to have the hybrid Japanese knotweed leaf shape.

 

The other parent being what, and how are they distinguished?

The leaves in the photos at the top do look a bit narrower than what I am used to seeing here in Britain. Will get some pics in the next fer days (weather permitting!)

 

http://www.google.com/search?q=gian...s=org.mozilla:en-US:official&client=firefox-a

 

Ah - Fallopia sachalinense.

Looks like the hybrid with F. japonica is known over here too, but is rare.