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Sapa Spruce Bog

No. 208


Photo by Thomas A. Meyer/DNR


Located in a glacial kettle hole, Sapa Spruce Bog features a black spruce-tamarack bog, the southernmost of this type in the state. It connects hydrologically in a clay-lined basin with a southern wet-mesic forest located to the northeast. The bog is more acidic than nearby Cedarburg Bog and contains many acid-loving species absent from its huge wetland neighbor. Surrounding the bog is a moat consisting of a sedge meadow in the southwest and swamp hardwoods in the north and east. Six species of sphagnum and several species that are disjunct from the main part of their range (outliers) grow here. The soil is Houghton muck, a very poorly drained soil developed in herbaceous debris overlying calcareous glacial drift. Sapa Spruce Bog is owned by the University of Wisconsin and was designated a State Natural Area in 1986.

Very few State Natural Areas have public facilities, but nearly all are open for a variety of recreational activities as indicated below. Generally, there are no picnic areas, restrooms, or other developments. Parking lots or designated parking areas are noted on individual SNA pages and maps. If a developed trail is present, it will normally be noted on the SNA map and/or under the Maps tab. A compass and topographic map or a GPS unit are useful tools for exploring larger, isolated SNAs.

The good majority of SNAs are isolated and have few or no facilities. Some SNAs have vehicle access lanes or parking lots, but their accessibility may vary depending on weather conditions. Parking lots and lanes are not plowed during winter. Hiking trails may be nonexistent or consist of undeveloped footpaths. A GPS unit or compass and a detailed topographic map are useful tools for exploring larger SNAs.

Non-DNR lands

Entrance fees: For non-DNR-owned SNAs, we are unaware of any vehicle or admission fees. However, please contact the landowner for more information.

Hunting and trapping

This is a non-DNR-owned SNA: Opportunities for hunting and trapping depend on the landowner. Please contact them directly to find out about their rules for hunting and trapping. You can find a link to other owner websites under the Resources tab.

Other activities

Other allowable activities such as - but not limited to camping, geocaching and bicycling are determined by the landowner. Please contact them directly or visit their websites for details.


Ozaukee County. T11N-R21E, Section 30. 24 acres.

Driving directions

From the intersection of State Highway 33 and County Highway I west of Saukville go west on State Highway 33 1.8 miles, then south on Birchwood Road 1 mile, then west on Knollwood Road 0.8 mile to the northeast corner of the site.

Please contact the UW-Milwaukee Cedar Sauk Field Station in Saukville for permission to use the area.

The DNR's state natural areas program is comprised of lands owned by the state, private conservation organizations, municipalities, other governmental agencies, educational institutions and private individuals. While the majority of SNAs are open to the public, access may vary according to individual ownership policies. Public use restrictions may apply due to public safety, or to protect endangered or threatened species or unique natural features. Lands may be temporarily closed due to specific management activities.

Users are encouraged to contact the landowner for more specific details. The data shown on these maps have been obtained from various sources, and are of varying age, reliability, and resolution. The data may contain errors or omissions and should not be interpreted as a legal representation of legal ownership boundaries. To create your custom map where you can zoom to a specific location, please use the DNR's Mapping Application.

Property Map [PDF]

Sapa Spruce Bog is owned by: The UW Board of Regents