Guide to Significant Wildlife Habitat - Door County Web Map

• Federally threatened dwarf lake iris occurs near Carp Lake (Judziewicz and Kopitzke 1999).
• Plum Island has been impacted by logging, but remains an aesthetic natural forested area because of
the absence of human presence. If left alone re-growth of vegetation could increase the aesthetic
value of Plum Island.
Washington Island
Washington Island is the largest of the Grand Traverse islands and covers approximately 35
square miles. It is located at the northern tip of the Door Peninsula. Four coastal wetlands are associated
with the island: Coffee Swamp, Jackson Harbor Ridges, and Big and Little Marsh. Development pressure
is strong throughout the island, including sensitive areas such as the high dolostone cliffs at Boyer Bluff.
Numerous, small private lots with houses coexist along the southeastern shore of the island along
with occurrences of alkaline rock shore communities. A number of owners have signed Protective
Agreements to safeguard this community and the plants that grow in it, including the federally listed
dwarf lake iris. Similar protection efforts would benefit other priority sites on the island (Judziewicz and
Kopitzke 1999).
• Washington Island is in the Town of Washington. They have adopted the county zoning ordinance.
• Upland and lowland hardwoods are dominant forest types. Conifer species including hemlock, white
spruce and balsam fir are present in varying degrees within hardwood stands. Lowland conifer stands
dominated by white cedar are also present. The quality of these forests is variable based on site
condition and past land use. Forest quality ranges from poor to good quality second growth.
• Land use is predominantly forested with lesser amounts of general agriculture, estate, single family
residential, recreational commercial, countryside, and mixed use commercial in the ferry dock area.
The Town of Washington has a population of 623 according to the 1990 census (Kasprzak and Walter
2001).
• Soils of Washington Island are mainly of two types. Most of the island, including the interior portion
contains soils shallow to deep, well drained, almost level to moderately steep. Sandy loam or loam
subsoil overlays sandy loam or fine sandy loam till or dolostone bedrock. The northeast tip and
southern shore contains soils that are deep and moderately deep, well drained to poorly drained, and
gently sloping to sloping. Fine sand or sandy loam subsoil overlay sand or sand and gravel outwash,
and very poorly drained, nearly level organic soil (USDA SCS 1978).
• Detroit Harbor is the south facing bay on the southwest section of Washington Island. This harbor
provides spawning habitat for smallmouth bass (Micropterus dolomieui), yellow perch (Perca
flavescens), and northern pike (Esox Lucius). Brown trout (Salmo trutta) are annually stocked in
Detroit Harbor (Corbisier 2000).
• West Harbor is located on the southwest side of Washington Island. It has approximately 50 acres of
water area lying below the normal high water mark of Lake Michigan. West Harbor is noted for its
diverse population of native aquatic plants and the minimal occurrence of invasive exotic plants.
Because high quality submerged aquatic species are rare in Lake Michigan this area is being reviewed
to become a state natural area by the WDNR. Known plants include flat-stemmed pondweed
(Potamogeton zosteriformis), milfoil (Myriophyllum spp.), Richardson’s pondweed (Potamogeton
richardsonii), wild celery (Vallisneria americana), Illinois pondweed (Potamogeton illinoensis),
muskgrass (Chara spp.), and coontail (Ceratophyllum demersum). Curly leafed pondweed
(Potamogeton crispus) an invasive exotic is also present. The plant community appears to support a
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Grand Traverse Islands