What grasses are invasive in Oregon?

Asked October 20, 2013, 1:51 PM EDT

Hi! I've heard rumors for a while, and with this month's issue of Fine Gardening, the rumors were confirmed. Miscanthus sinensis are NOT sterile. The article mentioned that the grasses are listed as invasive in over half of the US states, and although Oregon was not specifically mentioned, I have a hunch that we are one of them. The article made me wonder what other grasses are considered invasive here. Is there a comprehensive list of grasses to avoid? Thanks for your time and answer!

Multnomah County Oregon

2 Responses

I share your concern about the potential for possible invasive qualities of ornamental grasses and have asked that question of many knowledge persons. Miscanthus species aren’t a problem in western portion of Oregon or Washington. “Ornamental Grasses for Southwestern Washington” features an extensive chart of grasses for landscapes. http://clark.wsu.edu/volunteer/mg/gm_tips/OrnamentalGrass3.html

“…there appears to be more concern over its spread in the eastern half the United States than in the western half…” http://www.fs.fed.us/database/feis/plants/graminoid/missin/all.html

species aren’t included on the Oregon Invasive Species Council list of “100 most dangerous invaders to keep out” http://www.oregon.gov/OISC/Pages/most_dangerous.aspx.

Nor are they included on the Western US Invasive Plant EDRR Guide http://www.oregon.gov/ODA/PLANT/WEEDS/Pages/edrrweedguide.aspx#Grasses

Thank you for using Ask an Expert.

Thank you! That really helps! :)