Earth Partnership for Schools


General Characteristics

Distribution: Originally, lowland forests covered a total of 2,241,400 acres, or 6.4% total land surface of Wisconsin. Northern lowland forests are found on former lakebeds and river floodplains. Lowland conifer swamps frequently develop along meandering rivers or in small kettles, potholes, or large basins in glacial moraines or outwash. Several lowland conifer swamps are found in the southern portion of the state in glacial areas east of the Rock River and along streams dammed by glacial outwash in the Driftless area.

Physical Environment: Lowland forests are subject to flooding in late winter and early spring, high water tables, poor internal or surface drainage.

Microclimate: The topography of the lowlands creates a unique microclimate. Cold air drains into the lower elevations creating a dense night fog that bathes the plants in a moist atmosphere. As a result, lichens, mosses, and liverworts envelop the trunks of trees. In general, summers tend to be shorter, cooler and more humid; while winters are warmer, and temperatures fluctuate less than the surrounding highlands.

A spongy, organic substrate of peat also distinguishes lowland forests from other forest types. Dead, partially decomposed remains of mosses, sedges, or woody plants form peat. The peat substrate in the wet forest is highly acidic, very wet, and low in oxygen. Peat in the wet-mesic forest soil is less extreme and, as a result, organic matter is well decomposed, and texture is more uniform.

Composition: Berry producing shrubs are abundant. Black bears will frequently dine on cranberries, blueberries, snowberries, bearberries, viburnums, gooseberries, dewberries, dogwoods, and wintergreen. Poison sumac often borders lowlands, keeping humans out. Non-flowering plants, such as, mosses, liverworts, lichens, and ferns are prolific. Possibly 25 species of orchids grow in northern lowland forests.

Stability: Lowland forests are stable communities. These forests are capable of perpetuating themselves for a very long time. Fire and changes in water levels may destroy the lowland conifer swamps.