Apostle Islands Maritime Forests

State Natural Area (No. 266)

Location: Within the Apostle Islands National Lakeshore on Sand, Raspberry, Outer, Bear, and Devils Islands, Ashland and Bayfield Counties. T52N-R5W, Sections 12, 13 (Sand Island). T52N-R3W, Sections 18, 19; T52N-R4W, Section 24 (Raspberry Island). T53N-R1W, Section 13 (Outer Island). T53N-R3W, Section 33; T52N-R3W, Section 4 (Bear Island). T53N-R3W, Sections 10, 15 (Devils Island). 1093 acres.

Access: Islands are accessible only by water. Shuttle service to the islands via private carrier can be arranged through the Apostle Islands National Lakeshore headquarters in Bayfield, off State Highway 13. Entrance to the Devils Island unit requires the permission of private landowners to use their docks.

Description: Apostle Islands Maritime Forests consists of portions of five islands within the 21-island Apostle Islands archipelago. Soils on these sandstone-based islands vary from well-drained sands to poorly-drained clays, resulting in a variety of forest types. The cold waters of Lake Superior surrounding the islands greatly influence their vegetation. Except for Bear Island, deer are absent allowing hemlock and cedar to reproduce and Canada yew and other understory plants to thrive. The islands are owned and managed by the National Park Service. The Apostle Islands Maritime Forests were designated a State Natural Area in 1992.

Sand Island features a 167-acre northern wet-mesic forest with boreal affinities on the northeast tip of the island. A sparse canopy of huge (to 40 inches d.b.h.) white pine is mixed with yellow birch, red maple, white spruce, balsam fir, white cedar, and paper birch. The rare Chilean sweet cicely (Osmorhiza berteroi) is found here.

Raspberry Island’s natural area covers 273 acres of undisturbed northern mesic forest, northern wet-mesic forest, and undeveloped shoreline with sandstone and clay bluffs. A small sand spit on the island’s southeast shore encloses a sphagnum bog. The island’s interior forests contain virgin stands of white cedar and yellow birch with a shrub layer of mountain maple and yew. Balsam fir and paper birch dominate the island’s shoreline. Black and white warblers and black-throated blue warblers nest here.

The 202-acre Outer Island unit features undisturbed old-growth northern mesic forest, clay bank seeps, and ephemeral ponds on the northern tip of the island. The virgin hemlock-hardwood forest here is perhaps the most significant single stand of its type in the Upper Great Lakes region. It is truly spectacular. Dominants are hemlock, up to 44” d.b.h and aged at an astonishing 400 years, along with yellow birch and lesser amounts of white cedar, sugar maple, balsam fir, white spruce and mountain ash. Supercanopy white pines provide nesting sites for bald eagles. The understory contains thick beds of yew, bluebead lily, ferns, and clubmosses. The state-threatened marsh grass-of-Parnassus (Parnassia palustris) is found on the moist clay banks along the shoreline

Bear Island’s 188-acre unit contains a large northern mesic forest, portions of which are recovering from past disturbance. The undisturbed portions are old-growth, containing large hemlocks (to 30” d.b.h.) and yellow birch, along with white cedar, sugar maple, red oak and basswood. A perched bog, with northern wet and wet-mesic forest is also present.