Houghton's Goldenrod

Solidago houghtonii

Description

Houghton's goldenrod, Solidago houghtonii, is a large-headed goldenrod with lightly furred, slender stems that range from 8-30 in (20-76 cm) tall. Seven to 15 hairless (glabrous), three-veined linear leaves, up to 8 in (20 cm) long, are arranged alternately on the stalk. Leaves diminish in size toward the top of the stems. Inflorescences, consisting of flat-topped clusters of five to 30 golden flower heads, appear from midsummer until fall. One large specimen was observed with as many as 125 flower heads.

Habitat

Houghton's goldenrod is typically found on sparsely vegetated, shoreline flats and in damp depressions between sand dune ridges along Lake Michigan and Lake Huron. It occurs in waste areas directly behind lakefront dunes. This goldenrod is sometimes found in association with two other federally listed plants: Pitcher's thistle (Cirsium pitcheris ) and dwarf lake iris (Iris lacustris ).

Distribution

Houghton's goldenrod was discovered in 1839 along the northern shore of Lake Michigan in Mackinac County, Michigan. It is thought to be endemic to the northern shores of Lake Michigan and Lake Huron.

Houghton's goldenrod is presently found in 18 nearly contiguous shoreline populations in eight Michigan counties: Cheboygan, Chippewa, Delta, Emmet, Mackinac, Presque Isle, and Schoolcraft. It is also found at two sites in inland Crawford County. One population occurs within the boundaries of Camp Grayling, a training facility for the Michigan National Guard. Twenty-five populations are found on privately owned lands.

Canadian populations are found in the Manitoulin District and on Bruce Peninsula near Cabot Head in Ontario. The species is classified as Rare in Canada.

Although seemingly of widespread distribution, botanists are concerned by an abrupt decline in numbers of many populations and by the lack of reproductive vigor shown by others. At least 20% of historically known populations have disappeared since 1975.

Threats

Houghton's goldenrod is threatened by shoreline residential development and by increased use of dunes for recreation by hikers and off-road vehicles. Beach houses are typically built behind the dunes in the goldenrod's preferred location. Off-road vehicles churn the sands, destroying plants or preventing establishment of seedlings. High water levels at some lakeside sites have eroded beaches and destabilized dunes, reducing many plants to a non-flowering state.

Conservation and Recovery

Houghton's goldenrod is listed by the state of Michigan as Threatened, which generally prohibits taking, possession, sale, purchase, and transport of plants. The Nature Conservancy has initiated systematic monitoring of population sites.

The Recovery Plan recommends protecting the most viable populations and other essential habitat; surveying every population once a year; restricting off-road vehicles; promoting protection of the species by private landowners; designating Natural Area protection for some populations; encouraging land acquisition; and systematically assessing potential habitat from aerial photographs.

Contacts

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
Federal Building
Fort Snelling, Minnesota 55111
http://midwest.fws.gov/

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
300 Westgate Center Dr.
Hadley, Massachusetts 01035
http://northeast.fws.gov/

References

Guire, K. E., and E. G. Voss. 1963. "Distributions of Distinctive Shoreline Plants in the Great Lakes Region." Michigan Botanist 2:99-114.

Morton, J. K. 1979. "Observations on Houghton's Goldenrod (Solidago houghtonii )." Michigan Botanist 18:31-35.

Semple, J. S., and G. S. Ringius. 1983. "Solidago houghtonii Torrey and Gray." In G. W. Argus and D. J. White, eds., Atlas of the Rare Vascular Plants of Ontario. National Museum of Natural Sciences, Ottawa.

U.S. Fish and Wildlife Service. 1988. "Determination of Houghton's Goldenrod, Solidago houghtonii, to Be a Threatened Species." Federal Register 53(137): 27134-27136.

U.S. Fish and Wildlife Service. 1993. "Houghton's Goldenrod, Solidago houghtonii Recovery Plan." U.S. Fish and Wildlife Service. Ft. Snelling, Minnesota, 74 pp.