A methodology to determine appropriate forest herbs for restoration in second growth forests

Holt, Timothy J.
Richard Howents
Department of Environmental Studies
2002
!there has been a tendency to assume that these, often less conspicuous, [understory herbaceous] species will return to disturbed sites on their own once canopy development, litter accumulation and other forest features have reached a certain stage. This assumption that the less conspicuous components of forests will recover with the overstory over periods less than several hundred years has proven unfounded in studies in Denmark, England and the Northeastern US south through the Appalachians. In each case, the diversity and cover of forest herbs was found to be less in recently established forests than in older forests. This study develops a methodology to determine what forest herb species are associated with a given soil and over type combination, as well as where those herbs are present and absent. This methodology is intended as a starting point for restoration work in recovering successional forests where forest herbs may have been extirpated. This study does not, however, address actual methods for the reintroduction of forest herbs. On two soil types at Graften Lakes State Park, Rensselaer County, NY, I identified forty nine forest stands representing four soil and cover type combinations: Glover-steep (hardwood), Glover-steep (conifer), Brayton-level (hardwood) and Brayton-level (conifer). Thirty eight of these stands were surveyed for forest herbs. Rather than listing all forest herbs found within the thirty eight stands, I focused on uncommon forest herbs that tend to occur individually or in small groups, such as pink lady slipper (Cypripedium acaule) and maiden hair fern (Adiantum pedatum). Species which were extremely common in their respective stands such as Canada mayflower (Maianthmum canadense) and hay scented fern (Dennstaedtia punctilobula) were not noted. The surveys resulted in nine forest herb species associated with the Glover-steep (hardwood) stands and four species associated with the Brayton-level (conifer) stands. Three of the eight Glover-steep (hardwood) stands contained thrirty three percent or more of their associated forest herb species. The remaining five stands contained zero to thirty three precent of those herbs. Of the twelve surveyed Brayton-level (conifer) stands, four contained seventy five to one hundred percent of the forest herbs associated with this stand type, four other stands contained twenty five percent of these species and the remaining four contained none of the associated forest herb species. The findings indicate that Glover-steep (hardwood) stands have the greatest number of associated forest herbs, and that these stands are also the most likely to be missing these herbs. Brayton-level (conifer) stands contain only four associated forest herbs, but a greater percentage of these stands contain most of the species.

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