The relationship between microtopography and the presence and abundance of spring ephemeral wildflowers in southeastern Vermont

Hopkins, Paul
Peter Palmiotto, PhD
Department of Environmental Studies
2007
Starting 300 years ago, the New England landscape was altered when European settlers cut trees, eventually clearing up to 85% of the forests. Once without trees, the land was used for cultivation, grazing, and habitation. Signs of past land use, notably the absence of pit and mound complexes, can persist for many decades, even if trees are allowed to return. Also often absent from secondary forests are spring ephemeral wildflowers. The purpose of this thesis was to determine if there is a relationship between forest floor microtopography in a historically altered landscape and the presence and abundance of spring ephemeral wildflowers. A grid of 545 survey points connected by over 12 kilometers of belt transects was established on the 104 ac. Stephen Martin Memorial Wildlife Sanctuary in southeast Vermont to assess the presence of ephemeral wildflowers, their microhabitats, and the forest communities in which they grew. Six species were documented: Cardamine concatenate, Cardamine diphylla, Claytonia caroliniana, Dicentra Canadensis, Dicentra cucullaria, and Erythronium americanum. The survey determined that ephemeral wildflowers showed a prefence for pit, mound, side and niche microtopography, but not for terrain that had been leveled or was on a slope. These same species were more abundant in the Rich Northern Hardwood, Transitional Hardwood Limestone, and Dry Oak-Hickory-Hop Hornbeam communities. These forest communities both tended to grow in rich soils and showed the greatest change between spring and summer canopy cover. Steps can be taken to mitigate the effect of management activities on forest microtopography. However, sites which have experienced severe anthropogenic disturbance may take up to 500 years to recover and will likely do so with species different than were historically present.

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