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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Avenue, Room 1000, Portland, OR 97204

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How bad is it?

water primroseWater primrose patches along the Willamette have become quite large in places. In the Portland area, we know of several small to medium patches in the Columbia Slough system. A big part of the concern about these species is that aquatic and near-aquatic weeds treatment can be tricky. These are also fairly persistent species with substantial root reserves, which complicates treatment strategies.

Map of confirmed Ludwigia locations in Portland