1997-06-13_REPORT - M1981302 (11)

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In addition to the known range of the species, it is possible that undiscovered populations occur elsewhere in Wyoming (southeastern quarter, along the Green River upstream of Flaming Gorge Reservoir, along the Laramie Divide, along the Powder River and tributaries, and along the Cheyenne River) , Colorado (Pawnee grasslands area in the northeast, west slope - especially northwest portion, and along the base of the Front Range between Fort Collins and Pueblo) , Montana (Missouri River tributaries such as the Jefferson and Yellowstone Rivers) , and Utah/Nevada/Idaho (Uinta Basin, north of the Wasatch Front along tributaries, such as the Bear River, flowing westward toward the Great Salt Lake or Snake River in Idaho, low elevation wetlands in western Utah and Nevada in similar habitat to the Callao occurrence and the historical occurrence at Panaca) . D. Life History/Demography Very little is known about the life history and demography of the Ute ladies'- tresses. Research was initiated in 1991 at Dinosaur National Monument and in 1986 at City of Boulder Open Space to learn about life history, demographics, habitat requirements, and habitat management. The following information includes preliminary results from that research and associated literature searches, as well as observations from others who have worked with the orchid over some years. Orchids generally have very small seeds requiring specific symbiotic associations with mycorhizal fungi for germination (Arditti 1992) . Many species of Soiranthes are initially saprophytic, underground plants that persist for many years before leaves emerge above ground. The mycorhizal stage is reported to last for 8 years in Spiranthes soiralis, and green leaves are first produced 11 years after germination (Wells 1967, 1981) . The fungal associate may still play an important role in the survival of mature plants. Nutrients derived from a fungal symbiont may allow some orchid species to remain underground without above ground growth for one year or longer. S. soiralis individuals rarely flower in consecutive years or under unfavorable conditions, and may survive due to their relationship with mycorhizal fungi (Wells 1981) . S. diluvialis may have a similar life history (Tamara Naumann, City of Boulder Open Space Department, pers. comm. 1991) . Observations of individually monitored Ute ladies'-tresses plants in Utah and Colorado have demonstrated that a plant can remain dormant (without above ground growth) for at least one growing season (Arft 1993, Lynn Riedel , National Park Service, to litt. , 1993) . Studies of S. magnicamporum in western Kansas and Nebraska report that the orchid may bloom as rarely as once in 20 years (Magrath 1973) . The mean expected life span (longevity) of S. spiralis plants studied by Wells (1967) over a nine year period was calculated to be more than 50 years. Vegetative plants average between 10-15 cm in height, but can reach up to 35 cm. The inflorescence begins to emerge in June or July and can reach 12-45 cm tall , producing tubular white flowers arranged in a spiral . The orchid typically begins flowering at the end of July and continues until early September, depending upon moisture and light conditions. Shaded plants tend to flower later. Fruit set occurs in late August through September (Jennings 1990, Arft 1993) . At the end of the growing season, small (0.5-2 cm) leaf rosettes often emerge at the base of orchid plants and persist through the 6