Dear Ms. Streng, Thank you for taking the time to report this population of Ludwigia at First Lake in Albany. I've forwarded the information to Rick Barnett who works with for the City of Albany and who previously noted Ludwigia growing upstream at Waverley Lake. It's difficult to tell which species of Ludwigia this is without any fruit capsules (these form later in the summer), but it's most likely Ludwigia hexapetala which has been in the Willamette River for many decades.

Given the amount of this weed in the river system and the fact the seed and plant fragments can be moved by water and/or waterfowl, it would take a large, coordinated effort to control all of the Ludwigia in the valley. So, I'm unsure if the City of Albany will undertake any control measures at this site. But your assistance at identifying this noxious weed, as well as the yellow flag iris, are greatly appreciated.

If you have any questions, please let me know.

Best Regards,
Vanessa Morgan
Portland State University, Center for Lakes and Reservoirs

Vanessa Howard Morgan
June 7, 2011, 3:46 a.m.