THE VASCULAR FLORA OF HOG ISLAND, CHARLEVOIX COUNTY, MICHIGAN

摘要

The vascular flora of Hog Island, the fourth largest island of the Beaver Island Archipelago, was inventoried. Up to now, some vascular plants have been collected on Beaver Island, but few specimens have been collected from the surrounding islands of the Beaver Island Archipelago. A Floris-tic Quality Index (FQI) value of 92.7 was calculated, indicating that the island is representative of Michigan's pre-settlement flora. Three hundred and forty species, representing 77 families and 213 genera were collected over three field seasons (2000-2002) with collecting trips made in the spring, summer, and fall. These data were compared to data previously published for the Beaver Island Archipelago. Seventy-three percent of the plant families, 60.5% of the genera, and 43.4% of the species found on the Beaver Island Archipelago as a whole were also found on Hog Island. Among the collections were the threatened species Cirsium pitcheri, Iris lacustris, and Tanacetum huro-nense; Cypripedium arientinum, a plant of special concern; and the endangered Amerorchis rotundi-folia. Seventeen species not previously recorded for the Beaver Island group were documented.