Vegetational gradients and proximity to woodchuck (Marmota Monax) burrows in an old field [Gradients de végétation et proximité des terriers de la marmotte américaine (M. Monax) dans les champs anciens].

Résumé

Comparison of vegetation near and distant from 10 woodchuck (Marmota monax) burrows in a diverse field 6 years old revealed differences at both community and species levels. Total plant cover increased with distance from burrows. Species-richness was low near and distant from burrows and relatively high at intermediate distances, a result consistent with the intermediate disturbance hypothesis. Horsenettle (Solanum carolinense), Kentucky blue-grass (Poa pratensis), and fescue (Festuca elatior) increased, and orchardgrass (Dactylis glomerata) decreased with distance from burrows. While woodchucks strongly affect only a small fraction of the field (ca. 2%), they are important agents in creating a vegetational mosaic and in creating source areas for species of colonizing plants.