Solidago houghtonii

This is the record for Solidago houghtonii in the narrow sense, not including S. vossii, following Laureto and Pringle (2010).

Houghton's Goldenrod is a species that is mostly limited to shoreline habitats and alvars (flat limestone outcrops) within a small geographic range, but which can be relatively common where suitable habitat exists. Most extant sites are on the shores of Lake Michigan and Lake Huron, there are 75 sites in Michigan. It is also known from 33 sites in Ontario, Canada and from one disjunct population in western New York. Some sites are protected on Michigan State Parks and State Forests, Hiawatha National Forest, Ontario Provincial Parks, and other nature preserves. This species is threatened by habitat loss or modification due to residential development and recreational off-road vehicles, invasive exotic plants, quarrying, deer browse, and high lake levels in the Great Lakes. At least 20 percent of the historically known populations of this species have disappeared since 1975.

Houghton's Goldenrod occurs in the Great Lakes region of the United States and Canada. It occurs in coastal areas of northern Lake Michigan and northern Lake Huron, along the most northern coast of the Lower Peninsula and the southern coast of the Upper Peninsula of Michigan. It also occurs in Ontario, its range extends east to Manitoulin Island, Bruce Peninsula and it occurs disjunct in western New York (Bassett and Higman 2019, CWS 2014, Flora of North America Editorial Committee 2006, NatureServe 2022, Voss 1996)

There are about 110 occurrences of Houghton's Goldenrod known, 75 in Michigan, 33 in Ontario, and one in New York (Bassett and Higman 2019, CWS 2014, NatureServe 2022).

Threats to Houghton's Goldenrod include dense, coastal residential development, which includes loss of habitat, fragmentation and disruption of the naturally-occurring dune formation cycle, through the development of roads, retaining walls, etc. It also faces threats from off-road vehicles, and other recreation-related disturbances. Great Lakes levels have been high for several years prior to 2019 reducing potential habitat for Houghton's Goldenrod. If high lake levels persist, populations along the Great Lakes shorelines will continue to be threatened, including by dune destabilization. Invasive plant species also threaten some populations, especially in Michigan, Phragmites australis ssp. australis (common reed) and Typha spp. (cattails), and various exotic plants in alvar habitat in Ontario. Quarrying for limestone, and drought are also threats in the alvar habitat in Ontario (Bassett and Higman 2019, CWS 2014). Deer browse has also been identified as a threat (CWS 2014, Leopold and Weber 2019, USFWS 2020). Roadside right-of-way maintenance (pavement recycling, shoulder widening, herbicide application, shoulder grading, mowing, salting, etc.) continues to threaten populations.