Department of Environmental Studies
Neottia bifolia (Raf.) Baumbach, the Southern Twayblade, is a diminutive species of orchid that has an extensive range from the gulf coast of Texas to Nova Scotia. It is listed as endangered in five of the twenty states and in every province where it is found. The first Massachusetts population was recently discovered on the island of Martha's Vineyard. Data was collected on soil and vegetation composition of two populations of N. bifolia located on Martha's Vineyard in order to describe the habitat where this orchid is found in Massachusetts. The percent cover of the vegetation, soil characteristics and canopy cover were found to be extremely variable and thus not good indicators of orchid locations, however, both populations were found growing within a red maple and shrub swamp matrix amid similar species composition. The overstory of both sites is dominated by red maple, with predominantly a sweet pepperbush, highbush blueberry and swamp azalea shrub understory and a variable herbaceous layer. The results of this study can aid in discovering additional N. bifolia populations; provide information to facilitate the conservation of appropriate habitat elsewhere in New England; provide insight into appropriate habitat management; and suggest areas where further study is needed.