Fringed gentian is a characteristic species of wet prairies, and we found it in a newly restored area of our marsh (details below).
Fringed gentian |
Restoring a wet prairie: Our wet prairie is part of a much larger wetland that is present in the valley of Elvers Creek and East Blue Mounds Creek. Our part of the watershed is a side branch that runs up Pleasant Valley. In addition to a cold-water stream, we have a number of substantial springs that feed the area. The photo below provides an overview of the area where the gentian is present.
Sedge meadow where fringed gentian grows |
Originally, this area was a monoculture of Carex trichocarpa, a rhizomatous sedge which forms thick, dense patches through which nothing else can grow. About five years ago, I discovered a relationship between this sedge and lousewort (Pedicularis lanceolata), a hemiparasitic plant (related to wood betony). Although lousewort does not kill the sedge outright, it sets back its growth significantly, making it possible for many other wetland species to grow. We have a good lousewort seed source here and spread the seed into the Carex areas. The link given above and those links it refers to describe the work.
Once the sedge was under control, lots of other wetland species got started. But this was only part of the story. We needed fire to complete it.
Originally our wetland was burned only as part of a large burn of the whole area. Although this was very beneficial, the space between burns was 3-5 years. This year we decided to introduce annual burns in our piece of the wetland, focusing primarily on the long strip of C. trichocarpa that borders the Valley and Barn Prairies. This was a successful burn, and there has been a great response by the vegetation, as the photo above shows.
One of the outcomes of controlling the Carex was this first appearance of fringed gentian. (The seed came from a wet-mesic site elsewhere in Dane County.)
Since fringed gentian is an annual/biennial, its continued presence will depend upon good seed production and subsequent germination and growth. Unfortunately, we won't have a lot of control of that.
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