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THE MICHIGAN BOTANIST
Vol. 44
states that hogs were put on the island to eat the overabundance of water snakes found on the island.
The second story says instead that hogs were placed on the island to forage until butchering time. Evidence is lacking to support either story.
Methods:
Vascular plants were collected from Hog Island in the spring (7-10, 24-25 May 2000; 17 May
2001), summer (7, 16-18 July 2000; 25 June 2002), and fall (19 August 2000; 14 September 2001).
In order to obtain as complete an inventory as possible, all plant community types predicted to be
found on the island by MNFI were searched during spring, summer, and fall. Angiosperms, except
for some trees, were collected in flower or with fruits. Gymnosperms were collected without cones,
and pteridophytes and their allies were collected with sporangia when possible. Voucher specimens
for all taxa listed below are housed in the Central Michigan University Herbarium (CMC). Nomenclature generally follows Michigan Flora vol. 1-3 (Voss 1972; 1985; 1996) for gymnosperms, monocots, and dicots and Flora of North America vol. 2 Pteridophytes and Gymnosperms (Flora of North
America Editorial Committee 1993) for ferns and fern allies.
A database of vascular plants reported for the islands of the Beaver Island Archipelago was created, based on data from Veldman and Wujek (1971) and Voss (1972; 1985; 1996). The numbers of
taxa (families, genera, species) found on Hog Island were compared to the numbers of taxa found in
the rest of the archipelago.
The Floristic Quality Index (FQI) for Hog Island was calculated following the method described
in "Floristic Quality Assessment with Wetland Categories and Computer Application Programs for
the State of Michigan" (Herman et al. 1996). The above-mentioned procedure is a standardized, repeatable method of determining the floristic quality of an area based upon the native plants found at
the site. Native plants have been assigned a coefficient of conservatism (C) value based on the plant's
tolerance of disturbance and the fidelity it shows to presettlement-like habitats. The C values range
from zero to ten, with zero being associated with the highest disturbance tolerance and least fidelity
and ten being associated with the least disturbance tolerance and the greatest fidelity (Herman et al.
1996).
RESULTS
In all, 340 species were collected from Hog Island; included were 17 species
not previously reported for the Beaver Island Archipelago (see annotated list).
These species represented 77 families and 213 genera. The largest families were
Asteraceae (37 species), Cyperaceae (34 species), Poaceae (20 species),
Rosaceae (17 species), Orchidaceae (15 species), and Liliaceae (13 species). The
largest genera were Carex (22 species), Juncus (eight species), and Equisetum
and Salix (six species each). State threatened species Cirsium pitcheri (Pitcher's
thistle), Tanacetum huronense (Lake Huron tansy), and Iris lacustris (dwarf lake
iris) were collected, as was a species of special concern, Cypripedium arietinum
(ram's head lady-slipper). Only one endangered species, Amerorchis rotundifolia
(round-leaved orchis), was collected (Michigan Department Natural Resources
1987). A new population of Iris lacustris, in addition to the population previously noted (D. Albert, personal communication), was found (45046'37.4"N
85021'59.3"W). Forty-two of the 340 species collected on Hog Island were exotic species (12.4% of the Hog Island flora). The Asteraceae contained the greatest number of exotic species (11 species), with four each for the Brassicaceae,
Fabaceae, and Poaceae. The FQI value, based on the 298 native species found on
Hog Island, was 92.7.
