Rock River Canyon Research Natural Area

[photo:] Rock River Canyon`s Sandstone Cliffs; USDA Forest Service Photo by Andrea Denham (2014)

Rock River Canyon RNA features an excellent example of essentially virgin northern hardwood stands containing sugar maple (Acer saccharum), American basswood (Tilia americana), and some American beech (Fagus grandifolia). This forest surrounds a 200-foot-deep, ¼ mile wide canyon with nearly vertical sandstone cliffs which are soft and easily eroded. Rock River, a remnant of the drainage of glacial Lake Duluth, runs through the canyon. Floristic composition of the stand is diverse due to the change in gradient and the unmodified character of the area. *Found in Rock River Canyon Wilderness Area

Ecological Information

Physical and Climatic Conditions

Nearest weather station, with distance and direction from RNA:
Chatham Experimental Farm station, (I.D. # 201486, latitude 46 ̊20’N, longitude -86 ̊55’W). The station is about five miles due southeast of the RNA.
Annual precipitation (type, seasonal distribution) :
Annual precipitation averages 33.3inches (84.7cm);24% received during the growing season. Average seasonal snowfall is 178.6 inches (453.6cm).
Maximum and minimum temperatures:
Daily summertime temperatures average 51° F; average daily maximum temperatures average 52.3° F. Average temperature in the winter is 36.4° F; average daily minimum temperatures average 30.2° F.
Elevations range from 727 feet (221m) to 947 feet (288 m) MSL
Geology and Soils:
The RNA is located in the Central Lowland physiographic region and is characterized by Munising Formation and Jacobsville Sandstone bedrock with a surficial geology of thin to discontinuous glacial till over bedrock, glacial outwash sand, and gravel.
The northeastern plateau of the RNA is represented by Munising sandy loam at 0 to 6 percent slopes. This soil is moderately drained with moderately available water capacity above the fragipan. The south side of the Rock River Canyon is represented by Carbondale series. These soils were formed in depressions on till plains and are composed of organic material that can reach a depth of up to 51 inches (129.5 cm) with a medium acid to alkaline reaction.Shallow soils of the Onota-Deerton complex are found along the North Slope bordering Rock River.
Aquatic Features:
The Rock River is approximately 20-ft wide (6.1 m) with a moderate current. The river is relatively shallow and rocky and therefore not easily navigable by kayak or canoe. Within the RNA, Rock River is confined by steep canyons, and there are no wetlands along this stretch.

Ecological Classification & Inventory

Laurentian Mixed Forest Province, 212S Northern Upper Peninsula
212Sc Suomi Tilland Outwash Plain
Landtype Association
Onota Channelized Moraines
National Vgetation Classification:
Class Forest and Woodland
Subclass Temperate Forest
Formation Cool Temperate Forest
Division Eastern North American Cool Temperate Forest
Macrogroup Northern Mesic Hardwood and Conifer Forest
Group Northern Hardwood-Eastern hemlock-Eastern white pine Forest
*Association Acer saccharum-Tilia Americana/Ostrya virginiana/Lonicera Canadensis
Forest [CEGL002458] *Majority of RNA is in this association

View or download Complete Plant List (pdf)

MI Natural Community Types:
Rock River Canyon RNA is primarily composed of Mesic Northern Forest (66% of the total area) and Limestone Cliff (26%).
Common Flora:
Beaked hazlenut (Corylus cornuta), eastern prickly gooseberry (Ribes cynosbati), northern maidenhair (Adiantum pedatum), wild sarsasparila (Aralia nudicaulis), blue cohosh (Caulophyllum thalictroides), Dutchmen's breeches (Dentaria cucullaria), jewelweed (Impatiens capensis), Canada mayflower (Maianthemum canadense), sweet cicely (Osmorhiza claytonii), false Solomon's seal (Smilacina racemosa), starflower (Trientalis borealis), trillium (Trillium grandiflorum), downy yellow violet (Viola pubescens).
Common Mammals:
Common mammals include coyote (Canis latrans), Eastern chipmunk (Tamias striatus), raccoon (Procyon lotor), red squirrel(Tamiasciurus hudsonicus), and white-tail deer (Odocoileus virginianus)
Common Bird Species:
some of the common bird species include Yellow-bellied sapsucker (Sphyrapicus varius), Hairy woodpecker (Picoides villosus), Hermit thrush (Catharus guttatus), ovenbird (Seiurus aurocapilla), bluejay (Cyanocitta cristata), white-breasted nuthatch (Sitta carolinensis),and American crow (Corvus brachyrhynchos).
Potential Research Topics:
Rock Rive rCanyon RNA provides a diversity of fauna and flora to study in detail or in conjunction with climate change research and its effects on northern hardwoods and refugia sites.The stream system and non-acid moist cliffs provide opportunities for studies on amphibians, reptiles, or bats endemic to the RNA.

Related Reports and Publications

Emerick, L. L.; 1989; Ornithology Survey of Rock River Canyon Wilderness.Unpublished reportfound on file at the Forest supervisor’s office, Gladstone, Michigan.

Haas, Skye; 2014; Fauna surveys. Unpublished report found on file at the Forest supervisor’s office, Gladstone, Michigan.

Hall, Christinr; 2016; Establishment record for Rock River Canyon Research Natural Area, Hiawatha National Forest, Rapid River District, Delta County, Michigan. 35pp.

Kimball, J. C.; 1977; An Archaeological Inventory and Evaluation of Lands in the Rock River Canyon Wilderness Area.Michigan Natural Features Inventory.

NGDC. National Geographic Data Committee; 2012; National Vegetation Classification Standard (NVCS). Available online: Accessed May 2012.

USDA Forest Service; 1986; Rock River Canyon cRNA evaluation report. Unpublished Report on file at the Forest supervisor’s office, Gladstone, Michigan.

Last Modified: August 19, 2021