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Wisconsin State Natural Areas Program Butler Lake Flynn's Spring (No. 257)

Butler Lake Flynn's Spring

Photo by Deb Harder



Within the Northern Unit of the Kettle Moraine State Forest, Sheboygan County. T14N-R20E, Section 20. 163 acres.



Butler Lake and Flynn's Spring features a seven-acre shallow hard-bottom lake surrounded by sedge meadow. Previously, the site contained a tamarack hardwood swamp but a few years of high water levels has killed off most of the trees. Although the groundlayer has also been flooded, the aquatic vegetation and geologic features are still intact. Nearby Flynn's Spring is a small, spring brook flowing into the south end of Butler Lake. Chara covers the marl-bottomed Butler Lake while the dominant submerged aquatic species is Illinois pondweed. Emergents include white water-lily, bull-head pond-lily, and hard-stem bulrush. A small zone of sedges and bulrushes on the north end is the only open wetland. Older tamaracks, which formerly surrounded the lake, have died but the species is reproducing well along the northwestern and southern shores. Adjacent to the lake is Parnell Esker, a geologic feature known worldwide and used extensively for education. The esker is 5 to 35 feet in height and runs northeast southwest for about four miles. The lake and wetlands provide habitat for some uncommon invertebrates. Butler Lake and Flynn's Spring is owned by the DNR and was designated in 1992.


Driving directions

From the intersection of State Highway 67 and County Highway F in Dundee, go east on F one mile, then north on Division Road 1 mile, then east on Butler Lake Road 1.1 mile, then south on an access road 0.1 mile to a parking area, boat launch, and trailhead for the Butler Lake Trail. The wetlands are best accessed by canoe.


Butler Lake Flynn's Spring is owned by:

  • WDNR


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.

Entrance fees: Excepting Parfrey's Glen, the Cambrian Outlook in the Dells of the Wisconsin River, SNAs within State Parks and some within State Forests, all other DNR-owned SNAs do not have any admission fee. For more information, see Wis. Admin. Code NR 45. For non-DNR-owned SNAs, we are unaware of any vehicle or admission fees. However, please contact the landowner for more information.

Allowable activities

In general, the activities listed below are allowed on all DNR-owned SNA lands. Exceptions to this list of public uses, such as SNAs closed to hunting, are noted under the "Access" tab above and posted with signs on site.

  • Hiking
  • Fishing
  • Cross country skiing
  • Hunting
  • Trapping

Prohibited activities

Although a handful of sites allow activities like primitive camping (e.g. Lower Chippewa River on sand bars) or horseback riding (e.g. S. Kettle Moraine), the activities listed below are generally prohibited on DNR-owned SNAs.

  • Camping and campfires
  • Collecting of animals (other than legally harvested species), non-edible fungi, rocks, minerals, fossils, archaeological artifacts, soil, downed wood, or any other natural material, alive or dead. Collecting for scientific research requires a permit issued by the DNR
  • Collecting of plants including seeds, roots or other non-edible parts of herbaceous plants such as wildflowers or grasses
  • Drones: Flying-related activities, including the use of drones, hang-gliders and model airplanes, are prohibited. Permission may be issued by the SNA Program for the use of drones for educational or research purposes.
  • Geocaching
  • Horseback riding
  • Rock climbing
  • Vehicles, including bicycles, ATVs, aircraft, and snowmobiles except on trails and roadways designated for their use

For rules governing state-owned SNAs and other state lands, please consult Chapter NR 45 Wis. Admin. Code [exit DNR]

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Last revised: Monday, March 27, 2023