a natural area by name.
a natural area by county.
Explore outdoors
and find places to go.
Use our interactive map
to find natural areas.
and help care for SNAs.
Contact information
For information on State Natural Areas, email:
State Natural Areas Program

Or leave a voicemail at 608-267-0866 for a return phone call.

Wisconsin State Natural Areas Program Big Eau Pleine Woods (No. 235)

Big Eau Pleine Woods

Photo by Thomas A. Meyer/DNR



Within Big Eau Pleine County Park, Marathon County. T26N-R5E, Section 13. T26N-R6E, Section 18. 87 acres.



Big Eau Pleine Woods is an old-growth northern mesic forest located on a sloping peninsula that projects south into the Big Eau Pleine Reservoir, an impoundment of the Big Eau Pleine River. Sugar maple dominates the old growth forest with basswood, yellow birch, hemlock, and red oak. The largest trees occur on a small hilltop with a younger mixed-species forest occurring on the slopes. The gently rolling moraine contains numerous tip-up mounds and fallen, decaying trees afford a variety of microhabitats for plants and animals. The understory is rich with a diversity of spring ephemerals such as trillium, violets, hepatica, and bloodroot. Big Eau Pleine Woods is owned by the Marathon County and was designated a State Natural Area in 1990.


Driving directions

From the intersection of State Highways 107 and 153 just east of Halder, go east on 153 0.3 mile to Eau Pleine Park Road, then south 6.3 miles to the parking area for the Giant Hardwoods Nature Trail west of the road.

Hunting and trapping are prohibited in this county park.


Big Eau Pleine Woods is owned by:

  • Marathon County


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 own custom map where you can zoom to a specific location, please use the DNR's mapping application.


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. Trails, if present, are typically undesignated footpaths. If a developed trail is present, it will normally be noted on the SNA map and/or under the "Access" 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 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 land owner. 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" heading above. More details regarding allowable uses of this non-DNR owned SNA may be posted, if available, under the "Access" tab above.

Back to Top

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.

Last revised: Monday, March 27, 2023