Habitat Types
Four Main Habitat Types: Prairie, Savanna, Woodland and OId Field. Of course, there are gradations between these habitats and these zones are of interest as well. The following is a description of these major habitats with some representative species.
Prairie The prairie consists of open space with less than 10% tree cover. Grasses and other sun loving, drought resistant flowering plant species (forbs) are the dominant ground cover with a few scattered shrubs above them. The scattered shady areas beneath trees and shrubs have a different species composition than the open areas and are more representative of savanna. Savanna Savannas have more tree and shrub cover than prairies from (15 to 50 %). Plant species here are more shade tolerant and less exposed to light and wind. Grasses form less of the ground cover than in prairies but species from both environments are to be found. Savannas thus support a greater diversity of plants than prairies. Savannas may be thought of as the edges between prairie and woodland, a dynamic area where fire keeps the encroaching woodland at bay. At Alderville, oaks are the dominant trees with scattered Red Pine. Woodland Extensive tree and shrub layers define the woodland. While clearings exist in the woodland, overhead canopy generally exceeds 50%. Soils at the Alderville site are generally quite sandy and well drained. A mixed woodland consisting of Trembling Aspen, White Pine, White Birch, Red and White Oaks dominates. Extensive stands of Round-leaved Dogwood and Poison Ivy dominate the shrub layer. The woodlands here have all endured past periodic burns but their location adjacent to current housing locations has resulted in the recent suppression of fire. They are thus well established. Understory plants in such locations are both shade, and to a lesser extent, drought tolerant.
Old field habitats are formerly cultivated lands that are in various stages of the process of revegetating with both native and non-native plants. Many of the plants which pioneer the abandoned ground may be either native or non-native species either planted as forage crops or aggressive colonizers from nearby sources. The disturbance of deeper soil layers may also bring dormant seeds to the surface where they may sprout and begin to establish themselves. Certainly, herbaceous annual plants are among the first colonizers but even trees such as White Pine, Black Oaks and White Birches may arrive soon thereafter. Many of the plants seen in such habitats are non-natives such as Spotted Knapweed, Smooth Brome Grass, Canada Bluegrass and White Sweet Clover. Invariably, any native species present are prairie plants such as Big Bluestem, Indian Grass, Smooth Wild Rose and Butterfly Weed. Generally speaking, these habitats have the least diverse ecology
of the entire site. One of our objectives is to restore them to
more representative prairie and/or savanna habitats through burning,
weeding and reseeding.
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