What's Happening in Woody Plants?

Woody Plants is a field course, the likes of which you'll never experience again in your college career. This is an elementary course about plants and their natural history-their parts (morphology) and the organization of these parts (structure) that make a plant work (function). Becasue plants are inseparable from the ecosystems in which they grow, we never consider plants alone, but always in the context the place where they grow. So besides learning their identifying and fascinating parts, we'll have you begin to think about WHY they grow where they do. Therefore, we'll take you to some of the little known sites around southeastern Michigan--old-growth forests, ecosystems disturbed long ago and now looking natural, and plantings of uncommon and exotic species.

Woody Plants is an intensive and challenging course--the hardest course you'll ever love! Being out in the field in all kinds of weather for 4-5 hrs at a time with your team mates will undoubtedly be unforgettable. GSIs are cool and will help you develop a system of learning organisms and their natural history that you'll carry with you and use as a model the rest of your life. It's an introduction to learning organisms that are parts of life-giving Earth that sustains all of us.

The Ecosystem Approach to Woody Plants of Southeastern Michigan

One of the objectives of the course is to learn the plants where they occur natually in ecosystems of of southeastern Michigan. Although we focus on plant identification, it is important to emphasize that plants don't stand on their own. They are a part of ecological systems, in which they establish, grow, and reproduce. Plants are inseparable from the life-giving atmosphere, physiography, and soil. Each plant species, therefore, has a characteristic ecosystem or range of ecosystems of which it is an integral and notable part. Landscape ecosystems are segments or chunks of the earth's living skin--units of nature on the face of the earth. Any single perceptible ecosystem is a topographic unit, a volume of land and air plus organic contents extended areally over a part of the earth's surface for a certain time. Although we concentrate our study on the plants of these units, it is important at the outset to place them in an ecological framework so we can understand the physical site conditions where they grow. Because many of the plants we study have wide distributions, we find them growing in similar ecosystems in the upper Great Lake region, the midwest, or the northeastern U.S. and adjacent Canada. Thus, an understanding of the ecosystems of southeastern Michigan is not only a conceptual framework but provides understanding of plant-site relationships throughout much of eastern North America. In addition, we study and learn the major tree species that occur in five elevational zones of the Rocky Mountains in western North America. Many of these also occur in the Colorado Plateau (western Colorado, Utah, and adjacent areas of Idaho, Wyoming, Nevada, and New Mexico), the Sierra Nevada Mountains of California, the Cascade Mountains of the Pacific Northwest states of Oregon and Washington, and the boreal forests of Canada and Alaska. Therefore, the scope of the woody plants course includes regional ecosystems throughout North America, with special emphasis of their local distribution and natural history in Michigan.

Landscape ecosystems occur at different spatial scales. Thus we conceive the landscape as ecosystems, large and small, nested within one another in a hierarchy of spatial sizes. The ecosphere is the largest ecosystem we know, and it can be subdivided into ecosystems of different sizes. If we take as our focus a large regional landscape, the size of the state of Michigan, for example, it can be subdivided into a hierarchy of ecosystems. In Figure 1, we have done just that. By studying its climate, physiography, soil, and vegetation we divided Michigan's landscapes into three hierarchical regional types: Regions, Districts, and Subdistricts. Three additional hierarchical ecosystem levels incude the broad physiographic systems (outwash plain, moraine, ice-contact terrain, lake plain), the smaller landform-level ecosystems (pitted outwash plain, ground moraine, kame, kettle, beach ridge), and finally the thelocal landscape ecosystem types where we study the individual species in our field labs.

Our field work in Woody Plants takes place exclusively in Region I (Southern Lower Michigan) and District 1 (Washtenaw) of Lower Michigan (Figure 1). Within the Washtenaw District, however, we visit landscape ecosystems and study plants in three different subdistricts: Maumee (1.2), Ann Arbor (1.3), and Jackson (1.4). The Maumee subdistrict coincides with the lake plain of old Lake Erie and is characterized by flat terrain that was once (before drainage for agriculture) poorly drained except for sandy beach ridges. In Lab 4 at Lawrence Woodlot, we'll see the distinctive tree and shrub species of the seasonally wet sand lake plain.

The Ann Arbor Subdistrict (1.3 in Figure 1) is characterized primarily by fine and medium textured moraines. These are large features of glacial drift that were deposited by the Wisconsinan ice sheet as it stagnated in southeastern Michigan. The soil has a matrix of many fine particles (silt and clay) and is mixed with gravel, cobbles, and stones; this unsorted material is called till. Most of this land was cultivated because of its relatively good moisture status and high fertility. Beech-sugar maple forests once dominated the area, but now they are exceedingly rare. In our first lab at Miller's Woods, we'll see a small remnant of this landscape ecosystem type and its distinctive flora. Bird Hill (Lab 6) is a highly disturbed piece of moraine landscape. Radrick Forest (Lab. 2) is also located in this subdistrict and illustrates both till and outwash kinds of parent material.

Many of our labs (Waterloo Recreation Area, Lab 3; Haven Hill, Lab 4; Stinchfield Woods, Lab 9) are located in the Jackson Subdistrict (1.4 in Figure 1) where ice-contact terrain prevails. This landscape of hilly topography with many swamps and lakes supports an extremely diverse mosaic of ecosystem types and plants. Plants relegated to the dry ridges and slopes (black oak, northern pin oak) and those of poorly drained swamps (bog birch, poison sumac, leatherleaf) are in close juxtaposition to one another.

Throughout the course we'll be placing the plants we study in an ecological framework, the characteristic landscape or forest ecosystems where they grow and persist—their “home place.” Wherever you live and work, you can use this ecosystem approach as the basis for the study the plants of the area both regional and local contexts. This approach provides the basis for understanding where, when, and why plants grow where they do.