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Tonquin Geologic Area

Planning and conservation    Natural areas, parks and trails    Protecting natural areas    Acquiring natural areas    Tonquin Geologic Area

Oaks and kolks are two of the unique features found in this valuable wildlife corridor stretching between the Willamette River in Wilsonville and the Tualatin River Wildlife Refuge in Sherwood.

Goals and objectives

Learn about the goals and objectives for habitat and water quality protection in the Tonquin Geologic Area. View maps illustrating the Metro Council's priorities in this area and learn more about the importance of the area to our region.More

Acquisition improves habitat diversity, helps water quality and adds land to the future nature park

The Graham Oaks Nature Park isn't scheduled to open until next year but, thanks to a new acquisition by Metro, the park just got a little bigger – and a little better. The 2008 acquisition added 20 acres to the future park located north of Wilsonville Road and brings the total protected area to 250 acres. A small section of Mill Creek crosses the property, benefiting water quality in the Willamette River.

The Graham Oaks Nature Park anchors the southern end of the Tonquin Geological Area, a wildlife corridor with unique geologic features that stretch northward from the Willamette River to the Tualatin River National Wildlife Refuge in Sherwood. Three schools and residential developments (including the Villebois planned community) border the park.

Metro has been working to improve and restore native habitat and natural features at Graham Oaks since purchasing 230 acres in 2001. The acquisition adds to the parks large, mature Douglas fir forest and includes a small patch of rare Oregon white oak trees. Providing wildlife a mix of habitats is a key feature of Metro's plan for the natural area. Graham Oaks is already home to red-tailed hawks, deer and many other other animals.

Graham Oaks Nature Park set to open in 2010

Plans for the future park include trailheads, parking areas and nature trails to make the site accessible to the public. Interpretive signs will help visitors learn about the rare habitat that was historically found in the Willamette Valley and that is being re-created on the site. Park development is guided by a master plan completed in 2004. The City of Wilsonville, in cooperation with residents, Metro, Clackamas County and the West Linn-Wilsonville School District created the plan, which details the history and future management goals.

The future Graham Oaks Nature Park features a mix of forested canyons, streams, and seasonal wetlands and - until recently – open farmland. In January 2008, hundreds of thousands of plants, including 150,000 trees and shrubs were planted by Metro as part of an oak habitat restoration project. The restoration project is part of grant from the National Fish and Wildlife Foundation supporting rare habitats in the Portland metropolitan area.

The new plantings include dogwoods, willows, Oregon ash and Oregon white oaks, as well as many grasses and flowering plants including lupine and camas. All are native to the region. Many of the plants were grown from seeds harvested by Metro volunteers at other local natural areas. When these trees and plants have matured, they will provide habitat for wildlife including several bird species. Birds common to oak woodlands include the Western bluebird, white-breasted nuthatch, acorn woodpecker and Northern harrier hawk. View a video about the project

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Natural Areas Program

Related Links

Graham Oaks: A historical habitat renewed

Native American tribes harvested food at Graham Oaks, which was later farmed by ancestors of former Wilsonville Mayor Charlotte Lehan. The site's future was uncertain for some time, but Metro protected the land with two natural areas bond measures.

Graham Oaks Nature Park

Explore trails, restored oak woodlands, a conifer forest and rich wildlife at Metro's new Graham Oaks Nature Park in Wilsonville.

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