Dear Ms. Knopp,

Thank you for taking the time to report this. Yellow flag iris is, unfortunately, quite common in Washington county and many others along the Willamette Valley and the coast. I've notified Clean Water Services to see if there's any chance of treating this population, but due to the high number of invasive plants and limited budgets, most agencies are forced to focus on a few high priority plants - typically those that have not yet gotten so wide-spread (Japanese knotweed, giant hogweed, garlic mustard)

This information is still very valuable: establishing how widespread one invasive plant is can inform future management efforts. So, thank you for keeping and eye out on your neighborhood waterways!

Best Regards,

Vanessa Morgan
Portland State University, Center for Lakes and Reservoirs

Vanessa Howard Morgan
May 14, 2013, 6:17 a.m.