By Katherine Hollins, MNA Regional Stewardship Organizer – Eastern Lower Peninsula
MNA is fortunate to protect one of the top-ranked lakeplain wet-prairies in the state. This globally imperiled habitat is home to a beautiful diversity of plants, perhaps one of the most showy being the eastern prairie fringed orchid (PFO). MNA protects one of the largest populations of PFO and one of the few populations in the world that is considered long-term viable.
This beautiful, sweet-smelling orchid is a mysterious plant. It was once common in the state, but its population has declined to the point that it is now considered endangered by the state of Michigan and threatened by the federal government. This population decline is primarily due to habitat destruction. Many of the rich prairie soils were plowed into farm fields, and other areas were ditched or diked, altering the hydrology of the habitat that is so important to the plant. However, while we tend think of it as requiring extremely high quality habitats to survive, specimens have been found in roadside ditches and along the edges of mowed fields.
Historically, fluctuating lake levels helped support PFO habitat. High water pushes the orchid population inland, and prevents shrubs and trees from encroaching into the sunny prairie. When lake levels lower again, the orchid population moves back shoreward. Each year some plants are lost to too much or too little water and new ones are recruited where new suitable habitat is created. With land alterations, however, this ability to shift inland and shoreward according to the lake levels has been hindered.
Seasonal drought, lake level changes, and other factors influence the number of annually surviving plants, as well as the number of blooming plants. Individual PFO plants may not flower every year or may even go dormant when conditions are not favorable. In their PFO paper, Mike Penskar and Phyllis Higman say, “… the species is notorious for having large fluctuations in the number of flowering individuals from year to year.” Continue reading