Elk Rock Island is an island on the

Willamette River The Willamette River ( ) is a major tributary of the Columbia River, accounting for 12 to 15 percent of the Columbia's flow. The Willamette's main stem is long, lying entirely in northwestern Oregon in the United States. Flowing northward b ...

in the U.S. state of

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

. The 12- to 13-acre (4.9- to 5.3-ha) island, formed 40 million years ago by a volcano, was given to

Portland Portland most commonly refers to: * Portland, Oregon, the largest city in the state of Oregon, in the Pacific Northwest region of the United States * Portland, Maine, the largest city in the state of Maine, in the New England region of the northeas ...

by Peter Kerr in 1940. Note: Brochure funded by City of Portland Bureau of Environmental Services and Portland Parks & Recreation in cooperation with the Friends of Elk Rock Island and the Island Station Neighborhood in the City of Milwaukie. The city of Milwaukie took ownership of the park in April 2016. The island is accessible via Spring Park.

Ecology

The island contains deciduous forest, mixed evergreen-deciduous forest and perennial

graminoid In botany and ecology, graminoid refers to a herbaceous plant with a grass-like morphology, i.e. elongated culms with long, blade-like leaves. They are contrasted to forbs, herbaceous plants without grass-like features. The plants most ofte ...

vegetation. It is one of the last stands of the

Oregon White Oak ''Quercus garryana'' is an oak tree species of the Pacific Northwest, with a range stretching from southern California to southwestern British Columbia. It is commonly known as the Oregon white oak or Oregon oak or, in Canada, the Garry oak. It ...

References

External links

Radio program broadcast in 2012
Islands of the Willamette River Landforms of Clackamas County, Oregon Milwaukie, Oregon Parks in Clackamas County, Oregon {{ClackamasCountyOR-geo-stub