09159 - Thornapple

The Thornapple area encompasses 9,744 acres within the Chequamegon-Nicolet National Forest, centered on the headwaters of Log Creek and the Thornapple River drainage. Water is the organizing principle of this landscape: Log Creek originates within the area and flows through multiple forest types, its cold, clear current supporting specialized aquatic communities. The Thornapple River receives these headwater flows and carries them northward, draining a mosaic of wetlands, forested slopes, and seepage areas that collectively define the hydrology of this portion of northern Wisconsin.

Five distinct forest communities occupy different positions across the terrain. Northern Mesic Forest dominates the well-drained uplands, where sugar maple (Acer saccharum), northern red oak (Quercus rubra), and basswood (Tilia americana) form the canopy. On cooler, north-facing slopes and in coves, Hemlock-Hardwood Forest takes over, with eastern hemlock (Tsuga canadensis) and sugar maple creating a dense, shade-rich environment where the understory includes northern maidenhair fern (Adiantum pedatum), bluebead lily (Clintonia borealis), and threeleaf goldthread (Coptis trifolia). The wettest areas support Northern Hardwood Swamp, where black ash (Fraxinus nigra) and eastern hemlock grow among ostrich fern (Matteuccia struthiopteris) and plantainleaf sedge (Carex plantaginea). In the deepest peatlands, Black Spruce-Tamarack Bog emerges, with Wulf's peatmoss (Sphagnum wulfianum) forming the spongy substrate. Northern Wet-Mesic Forest occupies the transitional zones between these communities, where moisture and drainage create conditions supporting mixed hardwood and conifer growth.

The vertebrate predators here reflect the area's recovery as a northern forest ecosystem. The federally endangered gray wolf (Canis lupus) hunts deer across the forested landscape, while the federally threatened Canada lynx (Lynx canadensis) pursues snowshoe hares through dense hemlock stands. The federally endangered Northern Long-Eared Bat (Myotis septentrionalis) hunts insects in the canopy and understory at dusk. Brook trout (Salvelinus fontinalis) occupy the cold, spring-fed reaches of Log Creek, where they feed on aquatic invertebrates and serve as prey for the broad-winged hawk (Buteo platypterus) and barred owl (Strix varia). Wood frogs (Lithobates sylvaticus) breed in ephemeral pools within the swamps, their tadpoles forming a crucial food source for wading birds. The monarch butterfly (Danaus plexippus), proposed for federal threatened status, passes through during migration, dependent on milkweed plants in open areas. The purple wartyback (Cyclonaias tuberculata), near threatened (IUCN), filters nutrients from the flowing water of Log Creek and the Thornapple River.

Walking through Thornapple, a visitor experiences the landscape as a series of ecological transitions. Following Log Creek upstream from the Thornapple River, the forest canopy gradually closes as hemlock becomes more prevalent, the air cools, and the sound of water becomes constant. Climbing away from the creek into Northern Mesic Forest, the understory opens, light reaches the forest floor, and the character shifts to one of mature hardwoods. In the swamp areas, walking becomes slower; the ground becomes spongy underfoot, and the dense growth of black ash and hemlock creates a twilight environment even at midday. The calls of ruffed grouse (Bonasa umbellus) echo through the dense cover. In winter, the tracks of lynx and wolf cross the snow, evidence of predators moving through a landscape that is slowly returning to its pre-settlement ecological complexity.

The Ojibwe people, specifically bands of Lake Superior Chippewa, were the primary historical inhabitants of this region. Following a westward migration that brought them to northern Wisconsin approximately 400 years ago, they established a spiritual and economic center at Madeline Island in Chequamegon Bay. The Ojibwe were drawn to northern Wisconsin because it was the land where "food grows on water"—they harvested wild rice from the region's abundant lakes and slow-moving river sections. The Thornapple River and its tributaries served as critical water routes for travel; the Ojibwe navigated these waterways in lightweight birchbark canoes as part of a larger network connecting the Chippewa and Mississippi River systems. The area supported multiple subsistence practices: torch fishing was a central method, particularly in the nearby Lac du Flambeau region where an Ojibwe band led by Chief Keeshkemun migrated from Madeline Island in 1745 to establish a permanent settlement. Sugar camps or sugar bush lodges dotted the northern forests for harvesting maple sap, and the forest itself served as a storehouse for medicines, functional products like birch bark for canoes, and game. Through treaties signed in 1837 and 1842, the Thornapple area was ceded to the United States, though 11 Ojibwe tribes retained usufructuary rights to hunt, fish, and gather on these lands.

Prior to intensive timber extraction, the region's waterways supported a significant fur trading industry in the 17th and 18th centuries, with beaver, otter, and marten pelts as primary commodities. Between the 1860s and the early 1900s, the region underwent intensive commercial logging. Initial extraction focused on white pine from the "pineries," followed by hardwood and hemlock exploitation as railroad access improved. The expansion of logging into the interior was made possible by the construction of temporary logging railroads and spurs that allowed timber barons to reach hardwoods that could not be floated down rivers. Before permanent roads were established, "tote roads" were cut through the forest to transport supplies to logging camps via oxen and horse-drawn sleighs. Large lumber companies established transient logging camps that moved once local timber was exhausted.

The Weeks Act of 1911, as amended, provided federal authority to purchase lands for protecting navigable streams. In 1925, the Wisconsin legislature passed an Enabling Act granting the federal government permission to acquire and manage lands in the state as National Forests. Following the Great Depression, many private owners and farmers abandoned their land due to tax delinquency, and the federal government acquired these lands in the early 1930s. On March 2, 1933, President Franklin D. Roosevelt issued a proclamation establishing the Nicolet National Forest, which included several purchase units. The Thornapple area became part of the Chequamegon National Forest upon its official proclamation by the same order. In the 1930s, the Civilian Conservation Corps built fire towers, fire lanes, and early forest roads in the surrounding district to facilitate reforestation and fire protection. The current forest cover is largely the result of massive replanting efforts by the CCC during this era, producing even-aged second-growth forest. President Harry S. Truman enlarged both the Nicolet and Chequamegon National Forests through Executive Order 10374 in 1952 by adding lands acquired under the Bankhead-Jones Farm Tenant Act and the Weeks Act. The Wisconsin national forest system grew from approximately 409,000 acres in 1929 to over 1.5 million acres today through continuous acquisition of tax-delinquent and abandoned lands. The Thornapple area is now protected as a 9,744-acre Inventoried Roadless Area under the 2001 Roadless Area Conservation Rule and is managed within the Great Divide Ranger District of the Chequamegon-Nicolet National Forest.

Vital Resources Protected

Headwater Protection and Cold-Water Fishery Integrity

The Thornapple area contains the headwaters of Log Creek and the upper Thornapple River, a cold-water system that supports brook trout populations sensitive to thermal changes. The roadless condition maintains the riparian forest canopy that shades these streams and regulates water temperature—a critical function as climate change increases air temperatures and storm intensity across the region. Loss of streamside forest cover through road construction would expose flowing water directly to solar heating, raising temperatures beyond the narrow thermal tolerance of brook trout and other cold-water species dependent on this drainage network.

Interior Forest Habitat for Carnivores and Bats

The 9,744-acre unfragmented forest block provides essential habitat for three federally protected carnivores and insectivores: the federally endangered gray wolf and Canada lynx, and the federally endangered northern long-eared bat. These species require large, continuous forest interiors away from human activity and edge disturbance. Gray wolves and lynx depend on prey populations (deer, hare) that thrive in undisturbed forest structure; northern long-eared bats forage in intact canopy and roost in dead trees and crevices that persist only in forests without road-related mortality and salvage logging. Road construction fragments this habitat into smaller patches, isolating populations and reducing the area available for these species to hunt, den, and move across the landscape.

Ash and Hemlock Forest Composition

The Thornapple area contains black ash and white ash trees—both critically endangered (IUCN)—as well as eastern hemlock (near threatened, IUCN), which form the structural foundation of the Northern Mesic and Hemlock-Hardwood Forest ecosystems present here. These species are under severe pressure from invasive pests and disease. The roadless condition prevents the introduction and spread of invasive species (insects, pathogens, plants) that exploit disturbed soil and forest edges created by road construction. Once invasive species establish in a forest, they are extremely difficult to control; maintaining roadless status is a primary defense against further infestation of these already-vulnerable tree species.

Bog and Wetland Hydrological Function

The Black Spruce-Tamarack Bog and Northern Hardwood Swamp ecosystems within the area depend on intact hydrology—the natural movement and storage of water through soil and vegetation. Road construction, even at small scales, disrupts this hydrology through fill placement, drainage patterns, and altered snowmelt timing. Wetlands once degraded by hydrological disruption recover extremely slowly or not at all; the specialized plant and invertebrate communities (including the near-threatened purple wartyback mussel) that depend on stable water levels and chemistry cannot reestablish if the underlying water regime is permanently altered.

Threats from Road Construction

Sedimentation and Stream Habitat Degradation

Road construction requires cutting slopes and moving soil, which generates sediment that enters the drainage network through surface runoff and groundwater flow. This sediment smothers the gravel and cobble spawning substrate that brook trout require for reproduction, reducing egg survival and recruitment. In a headwater system like Log Creek, where the Thornapple area originates, sediment inputs from even a few miles of new road have measurable downstream effects on water clarity and benthic habitat quality. The cold-water fishery cannot recover until sediment inputs cease and the stream naturally clears—a process that takes years to decades depending on road maintenance and storm frequency.

Canopy Removal and Stream Temperature Increase

Road construction through forested terrain requires removing trees along the road corridor and at stream crossings to accommodate drainage and visibility. This canopy loss exposes flowing water to direct sunlight, raising water temperature—a direct, irreversible consequence in the short term. For brook trout and other cold-water species already stressed by regional warming trends, even a 1–2°C increase in summer water temperature can exceed their thermal tolerance and cause mortality or emigration. Because the Thornapple River system is already at the southern edge of brook trout range, temperature increases from road-related canopy loss would compress suitable habitat into smaller, isolated refugia.

Habitat Fragmentation and Carnivore Population Isolation

Road construction divides the 9,744-acre forest block into smaller patches separated by the road corridor itself and the edge effects (increased light, invasive species, human activity) that extend into adjacent forest. Gray wolves and Canada lynx require large, continuous territories to hunt and breed; fragmentation reduces the effective habitat available and isolates populations from one another, preventing genetic exchange and increasing extinction risk. Once a road is established, the fragmentation is permanent—even if the road is later closed, the edge effects and human access patterns persist, and the landscape's capacity to support large carnivore populations remains diminished.

Invasive Species Establishment and Spread

Forest roads function as corridors for invasive plants, insects, and pathogens—they are disturbed, well-lit environments where non-native species thrive and from which they spread into adjacent forest. For the critically endangered black ash and white ash trees already present in the Thornapple area, road construction would create entry points for the emerald ash borer and other pests that exploit road edges and disturbed areas. Once established, invasive species cannot be eradicated from a forest; the roadless condition is the primary mechanism preventing their introduction and spread. Road construction would guarantee the eventual loss of these already-vulnerable ash species from the area.

The Thornapple Roadless Area encompasses 9,744 acres of Northern Mesic Forest, Hemlock-Hardwood Forest, and Black Spruce-Tamarack Bog in the Medford-Park Falls Ranger District of the Chequamegon-Nicolet National Forest. Access to this roadless area is by foot only—motorized vehicles are prohibited—which preserves the quiet, undisturbed character essential to all recreation here. Hunters, anglers, and birders access the area from forest roads that border its perimeter, then travel on foot through interior trails and along stream corridors.

Hunting is a primary use in the Thornapple area. Ruffed Grouse and Woodcock inhabit the young aspen and alder habitat throughout the forest. White-tailed Deer and Black Bear are also present in the Northern Forest Zone. The Medford-Park Falls Ranger District maintains hunter walking trails as linear wildlife openings that provide foot access and clear sightlines for upland bird hunters. All hunters must follow Wisconsin DNR regulations for the Northern Forest Zone, including the nine-day gun deer season beginning the Saturday before Thanksgiving and archery seasons from mid-September through early January. Only portable tree stands are permitted, and they must be removed daily. The roadless condition is critical here: without roads, the area remains quiet and undisturbed during hunting season, and the absence of motorized access means hunters rely entirely on foot travel, preserving the traditional character of forest hunting.

Fishing opportunities center on the Thornapple River and Log Creek. The Thornapple River supports Smallmouth Bass, River Redhorse, Channel Catfish, Walleye, Northern Pike, and Muskellunge. Log Creek is a coldwater stream with Brook Trout. The adjacent Thornapple Flowage, a 266-acre lake accessible via two public boat landings, holds Musky, Panfish, Largemouth and Smallmouth Bass, Northern Pike, Walleye, Sturgeon, and Catfish. Anglers must follow Wisconsin DNR regulations; bass fishing is open year-round on a catch-and-release basis, while Walleye has a daily bag limit of 3 with specific length restrictions. Access to remote sections of the Thornapple River and Log Creek requires a hike of a mile or more from the area boundary. The roadless status protects the watershed integrity that sustains these fisheries and ensures that anglers can experience the river in a quiet, undeveloped setting.

Birding in the Thornapple area takes advantage of diverse forest and wetland habitats. Residents and breeders include Broad-winged Hawk, Barred Owl, Ruffed Grouse, Least Flycatcher, Red-breasted Nuthatch, Veery, and Hermit Thrush. Conifer specialists such as Blue-headed Vireo, Golden-crowned Kinglet, Northern Parula, Blackburnian Warbler, and Cape May Warbler are found in mature stands. The Black Spruce-Tamarack bogs support Winter Wren, Northern Waterthrush, and Canada Warbler. Spring migration in May brings Nashville, Yellow-rumped, Black-throated Green, and Chestnut-sided Warblers through the region. The Thornapple River corridor is recognized as a Conservation Opportunity Area that benefits species requiring large blocks of mature forest, including Northern Goshawk and Red-shouldered Hawk. Birding access is primarily via non-motorized travel along old logging roads and forest trails. The roadless condition preserves the interior forest habitat and unfragmented landscape that these species depend on, particularly during breeding season and migration.

Wildlife and botanical photography opportunities exist throughout the area. Potential subjects include American Marten, Ruffed Grouse, Broad-winged Hawk, Barred Owl, Wood Frog, Brook Trout, and Muskellunge. The area is documented habitat for Gray Wolf, Northern Long-eared Bat, and Canada Lynx. Native flora suitable for botanical photography includes sugar maple, eastern hemlock, northern maidenhair fern, bluebead lily, threeleaf goldthread, and ostrich fern. Wulf's peatmoss occurs in the bog ecosystems. The Thornapple River and Log Creek provide water feature subjects. The roadless designation means low light pollution and an absence of development that would otherwise degrade wildlife habitat and scenic values.