ForestTypes

Introduction	Forest Types
Forest Characteristics	Management
Forest Contributions	Special Considerations
The Forest Plan	Assistance

FOREST MANAGEMENT GUIDELINES FOR MICHIGAN
From the Michigan Society of American Foresters

Michigan Forest Types and Their Ecology

Though forests once covered about 95% of Michigan, today about half the state is forested [see Dickmann and Leefers (2003), The Forests of Michigan, for a thorough discussion of the state’s forest history]. But this forest cover varies by region: 21% of the southern Lower Peninsula is occupied by patchy woods and wetland corridors, whereas 65% of the northern Lower Peninsula and 84% of the Upper Peninsula are covered by large forested tracts. Within each region the combined effects of glacial landforms, climate, soil, and recent history have produced a variety of forest habitats (Table 1). On these unique habitats grow different forest types [see the field guide by Dickmann (2004), Michigan Forest Communities, for a complete description of Michigan forest types].

A forest type is a broadly defined ecosystem—a varied and complex community of plants, animals, and other organisms living together in a common habitat. Forest types are defined principally by their characteristic tree species. This practice does not imply that the organisms associated with these trees are somehow less important ecologically. Trees are large and structurally dominant, and they may have monetary value or aesthetic appeal; thus we focus on them. Michigan’s forests are very diverse, largely because of the extremely variable climate produced by the surrounding Great Lakes and the great south to north and east to west geography. Ten coniferous tree species and 52 hardwood or broadleaf deciduous tree species that reach commercial size are native to the state. Another 30 or so native species are considered small trees or large shrubs. A number of these large and small trees reach the northern extent of their range in the southern part of the state. But because of their unique, gene-based adaptations, these native tree species do not all grow together in the same habitat or the same geographic area of the state. Rather, in a given geographic region certain trees congregate together in a particular habitat to form a distinctive forest type.

A forest owner may learn that there are a number of different forest classification systems. For these guidelines, the forest type descriptions are grouped under three broad classes: Wetland Forest Types, Upland Forest Types and Open Canopy Forests. Forest plantations are also described.

Table 1. The continuum of forest habitats.

Ecological Description	Xeric	Dry mesic	Mesic	Wet mesic	Hydric
Average moisture during the growing season	Very dry	Somewhat dry	Moist	Very moist; water may stand in the spring	Wet
Drainage	Excessively drained	Very well-drained	Well-drained	Somewhat poorly drained	Poorly drained or undrained
Surface soil textures	Sand to loamy sand	Loamy sand to sandy loam	Sandy loam to loam	Loam to clay loam	Sand to clay loam; muck or peat
Natural fertility	Infertile	Moderately infertile to fertile	Very fertile	Fertile to moderately fertile	Moderately infertile to very infertile

Wetland Forest Types

The glacial landforms of Michigan, combined with normally abundant rainfall, have produced an abundance of wet (hydric) habitats, and many of these habitats are forested. Wetlands are protected under Section 404 of the Federal Clean Water Act of 1972 and Part 303 of the Michigan Natural Resources and Environmental Protection Act of 1994 (P.A. 451). These acts regulate the discharge of pollutants into wetlands, the building of dams and levees, infrastructure development, and the draining of wetlands for farming, forestry, or other purposes. While nearly all forest management is guided by “best management practices” (BMPs), which are designed to protect water and soil resources, these BMPs particularly impact management of wetland forests.

Southern Deciduous Swamps &Floodplain Forests
Northern Hardwood Conifer Swamps
Northern Cedar Swamps
Northern Conifer Bogs and Muskegs

Upland Forest Types

The extensive uplands of Michigan are of glacial origin. They include hilly ice-contact features—moraines, kames, eskers, drumlins, and crevasse fillings—as well as flat or gently undulating till plains, outwash plains, and well-drained former lakebeds. Near the shore of Lake Michigan and in some inland areas, wind-shaped sand dunes also occur. In the highlands of the western Upper Peninsula, ancient bedrock forms prominent, mountainous ridges. Upland habitats are extremely diverse, with local differences in climate and history adding their influence to habitat variation.

Southern Maple Beech Forests
Southern Oak-Mixed Hardwood Forests
Northern Maple-Mixed Hardwood Forests
Northern Hemlock Forests
Northern Oak Forests
Northern Pine Forests
Boreal Spruce-Fir Forests
Aspen-Paper Birch Forests
Plantations

Open Canopy Forest Types

Although not considered commercial forest types, small areas of open forests consisting of scattered or clumped trees—known as savannas or barrens—also occur in Michigan. They represent a transition between closed forests and prairies and are maintained by frequent disturbances, usually fire or grazing. Although they occupied more than 2 million acres in the state in the early 1800s, savannas are the rarest forest types in Michigan today. :

Southern lakeplain oak-hardwood openings
Southern oak barrens
Northern pine and oak barrens
Great Lakes barrens
Alvar savannas
Pine stump plains

Michigan SAF Home Page

This website is maintained by Bill Cook, Michigan State University Extension Forest in the Upper Peninsula. Comments, questions, and suggestions are gratefully accepted.

Last update of this page was 9 January, 2014

This site is hosted by School of Forest Resources and Environmental Science at Michigan Technological University.