Horseshoe Bay Research Natural Area

[photo:] Dukes RNA. Photo by Lucy Tyrrell, USDA Forest Service.

St. Ignace
2065 total; Southern unit 1710 and Northern unit 355
The RNA features cobble beaches, wooded dunes, northern fens, interdunal wetlands, rich conifer swamps, Great Lakes marshes, and hardwood-conifer swamps. Notable are extensive areas of shallow pools underlain by marl and occurring on both current and former shorelines of Lake Huron. A number of Federal and state listed species have been observed within the RNA, including four state threatened plant species: sedge (Carex scirpoidea), crowberry (Empetrum nigrum), hyssop-daisy (Erigeron hyssopifolius), northern meadow-rue (Thalictrum venulosum); one Federal and state threatened plant, Great Lakes goldenrod (Solidago houghtonii); the state threatened osprey (Pandion haliaetus), and the Federal and state threatened American bald eagle (Haliaeetus leucocephalus).

Ecological Information

Physical and Climatic Conditions

Nearest weather station, with distance and direction from RNA:
The nearest NOAA weather station is #1492 in Cheboygan, Michigan, which is 24 miles (38.6 km) from the approximate center of the RNA at the narrow west end of Lake
Annual precipitation (type, seasonal distribution) :
Average annual precipitation is 29.9 inches (76 cm), and average annual snowfall is 78 inches (198 cm).
Maximum and minimum temperatures:
Temperatures range from a mean maximum temperature of 78 ºF in July, to a mean minimum temperature of 7 ºF in February.
Elevation ranges from 585 to 600 feet (177-182 m).
Geology and Soils:
The quaternary geology is lacustrine sands and thin till over bedrock. The bedrock geology is Pointe aux Chenes Shale and St. Ignace Dolomite, which typically lie less than 50 feet below the surface. Soils of the south unit consist mainly of Markey and Carbondale mucks and Rosecommon mucky sand. The north unit contains Markey and Carbondale mucks, the Eastport-Rosecommon complex, Solona loam, Deford mucky loamy fine sand, and Ingalls fine sand.
Aquatic Features:
Martineau Creek and an unnamed stream flow through the south unit. The Carp River lies adjacent to the southern boundary of the north unit. An unnamed intermittent stream flows through the central area of the north unit. A high water table is a prominent feature, and ponds and standing water are common.

Ecological Classification & Inventory

Northern Great Lakes (212H)
St. Ignace Lake Plain (212Hj)
Plant Communities:
SAF Cover Types (list acres): Kuchler Types (list acres):
16 Aspen - (N-8) 84 G.Lkes Sprce/Fir (N-20), (S-124)
21 Eastern White Pine (S-16)
85 Conifer Bog (N-180), (S-1329)
25 Sugar maple - beech - yellow birch (S-30) 86 G.Lkes Pine (N-8), (S-16)
36 White spruce - balsam fir -paper birch (N-20), (S-98) 93 Beech/Maple (S-83)
37 Northern White Cedar (N-180), (S-1329)  
38 Tamarack - 26(S)  
39 Black ash - American elm - red maple (S-53)  

View or download Complete Plant List (pdf)

Common Shrub Species:
Bog-rosemary (Andromeda glaucophylla), chokeberry (Aronia melanocarpa), leatherleaf (Chamaedaphne calyculata), dogwood (Cornus sp.), trailing arbutus (Epigea repens), wintergreen (Gaultheria procumbens), black huckleberry (Gaylussacia baccata), creeping juniper (Juniperus horizontalis), swamp laurel (Kalmia polifolia), Labrador tea (Ledum groenlandicum), American alder-buckthorn (Rhamnus alnifolia), willows (Salix spp.), speckled alder (Alnus rugosa), bearberry (Arctostaphylos uva-ursi), bush honeysuckle (Diervilla lonicera), wintergreen (Gaultheria sp.), swamp red current (Ribes triste), rabbit-berry (Shepherdia canadensis), shrubby five-fingers (Potentilla fruticosa).
Common Herbaceous Species:
Spike rushes (Eleocharis spp.), crowberry (Empetrum nigrum), hyssop daisy (Erigeron hyssopifolius), bluejoint (Calamagrostis canadensis), sedges (Carex stricta and C.. aquatilis), sedges (Carex spp.).
Common Mammal Species:
Shrew (Sorex sp.), snowshoe rabbit (Lepus americanus), least chipmunk (Eutamias sp.), red squirrel (Tamiasciurus hudsonicus), deer mouse (Peromyscus maniculatus), muskrat (Ondatra zibethicus), porcupine (Erethizon dorsatum), coyote (Canis latrans), gray wolf (Canis lupus), black bear (Ursus americanus), American mink (Mustela vison), river otter (Lutra candensis), bobcat (Felis rufus), white-tailed deer (Odocoileus virginianus), moose (Alces alces).
Common Bird Species:
Bald eagle (Haliaeetus leucocephalus), osprey (Pandion haliaetus).

Related Reports and Publications

1996. Establishment Record of the Horseshoe Bay Research Natural Area within the Hiawatha National Forest. Unpublished report on file at the Northern Research Station, Rhinelander, 44 pages.

Last Modified: August 20, 2021