Purple Loosestrife

Purple Loosestrifes bloomed beautifully in Oaks Bottom park, Sellwood
  Purple Loosestrife
In the photo you see Purple Loosestrife at Oaks Bottom

Purple Loosestrife is a plant of European origin, has spread and degraded temperate North American wetlands since the early nineteenth century. The plant was introduced both as a contaminant of European ship ballast and as medicinal herb for treatment of diarrhea, dysentery, bleeding, wounds, ulcers and sores.
Scientific name: Lythrum salicaria

As you can in the photo they are wetland perennials. They can grow about heights of 2m with 30-50 stems forming wide-topped crowns that dominate the herbaceous canopy.A fascinating fact that one mature plant can produce more than 2 million seeds annually!

Oaks Bottom Wildlife Refuge located at SE 7th Ave & Sellwood Blvd, Portland Oregon.

Oaks Bottom Wildlife Refuge MAP
The park info:
Acreage: 141.22
Acquired in 1959
Land manager: Portland Parks and Recreationoaksbottom-map
Click for detail map here
Length: 4.43 miles
Park hours: 5:00am-midnight. North parking lot closed 10:00pm-5:00am.

More info: