Identify this reed
Have a reed/ bamboo type plant. Stems grow to 4-5' tall. Approx the diameter of your thumb. Stems are green w/ red splotches. The area they are in is full sun, ground varies dependent on rain. Can be very swampy or dry. Reeds don't flower, just leaves and appears like segmented bamboo.
Clackamas County Oregon weed identification
Thank you for your question. This is not a reed, but it's a weed! It appears to be a knotweed, which is labeled as a noxious weed in Oregon and throughout the United States. Here's a link to an OSU article about this plant and its control. It is difficult to eradicate.
I hope this is helpful to you. Good luck!