Houghton's Goldenrod |
Houghton's goldenrod is a showy goldenrod found only on the northern Great Lakes shoreline of Lakes Huron and Michigan. It is threatened by loss of habitat due to increased human activity in shoreline areas. Heavy foot and vehicular traffic along the shoreline represent major threats. Houghton's goldenrod is listed as a "threatened" species. Threatened species are animals and plants that are likely to become endangered in the foreseeable future. Endangered species are animals and plants that are in danger of becoming extinct. Identifying, protecting, and restoring endangered and threatened species is the primary objective of the U.S. Fish and Wildlife Service's endangered species program. Many people believe that goldenrod causes hay fever. Goldenrods are unfairly blamed because their showy flowers bloom at the same time as less conspicuous ragweed flowers that cause the itching and sneezing. In fact, goldenrod pollen is too heavy to be carried on the wind like tree pollen. Instead, goldenrod pollen is carried by the insects that pollinate the flowers and is not wasted on the wind or allergy sufferers. Houghton's goldenrod was named in honor of Douglass Houghton, a doctor, botanist, civic leader, and Michigan's first State Geologist. During the geological survey of Michigan in 1839, Houghton discovered this species of goldenrod in Mackinac County between what are now the communities of Naubinway and Epoufette, on the north shore of Lake Michigan. This showy, shoreline goldenrod grows nowhere else in the world but along the Great Lakes shoreline. It grows primarily along the northern shores of Lakes Michigan and Huron. Most populations of Houghton's goldenrod occur in Chippewa, western Mackinac, northern Emmet, Cheboygan, and northern Presque Isle counties. Outside of Michigan it extends to the Bruce Peninsula in Ontario, Canada. Houghton's goldenrod typically grows on moist sandy beaches and shallow depressions between low sand ridges along the shoreline. This habitat is called interdunal wetland. Fluctuating water levels of the Great Lakes play a role in maintaining this unique goldenrod. During high water years, colonies of Houghton's goldenrod may be submerged. When water levels recede some plants survive the inundation and new seedlings establish on the moist sand. Other attractive plants that often grow with Houghton's goldenrod include the creamy white Grass-of-Parnassus, the delicate blue Kalm's lobelia, the yellow-flowered shrubby cinquefoil, twigrush, and other goldenrods. This enchanting habitat displays a tapestry of color and texture that continually changes throughout the seasons. It is a unique habitat within the Great Lakes ecosystem. Like other goldenrods, Houghton's goldenrod is a perennial having an upright stem bearing many small, bright yellow flower heads that resemble tiny daisies, but are completely yellow. Unlike many other goldenrods, Houghton's goldenrod flowers are arranged in a more or less flat-topped branched cluster. The narrow leaves are up to 4.5 inches long, relatively few, and crowded toward the base. A characteristic helpful in identifying this goldenrod may be seen in the small flower stalks within each flower cluster. These stalks of the individual flower-heads are covered with tiny fine hairs. The bright yellow flowers bloom primarily in August and early September, but some plants may flower as late as October. There are two other goldenrods with flat-topped flower clusters that grow in the same habitat as Houghton's goldenrod. These "look-alikes", grass-leaved goldenrod and Ohio goldenrod, can be confused with Houghton's. These three species are the only goldenrods with flat-topped flower clusters found along the shores of the northern Great Lakes. Grass-leaved goldenrod has many more leaves along the stem, but lacks leaves at the base during flowering. Its flower-heads are distinctly smaller than those of Houghton's goldenrod. Ohio goldenrod is a larger species with broader, flat leaves and a dense, many headed flower cluster with smooth, non-hairy stalks of the individual flower-heads. The yellow "petals" in Houghton's goldenrod are distinctly larger than those in the other two "look-alikes." In addition to aesthetic, ethical, and ecological reasons for protecting Earth's diverse species, another reason can be offered: self-interest. The natural world is our life support system, providing countless medical, agricultural, and commercial benefits. For example, chemicals from plants are the sole or major ingredient in one-quarter of all prescription medications in the United States. Scientists have shown that closely related plants usually have similar chemical compounds. Stokes aster, an ornamental plant of the Southeast, in the same family as Houghton's goldenrod, yields a seed oil rich in epoxy fatty acids useful in the production of paints and other coatings. If we choose to save wild species now, they may offer us opportunities in the future. We do know that when a species becomes extinct, a unique set of genetic material whose use presently may be unknown, is lost forever. Source: Michigan DNR's Natural Heritage Program |