The History and Management of the Western Prairie Fringed Orchid at Pipestone National Monument

1. The History and Management of the Western Prairie Fringed Orchid at Pipestone National Monument

3. History • 1993 • random search for flowering plants; recorded height of inflorescence from the soil surface; flowers and flower buds counted • 1994 • all flowering orchids marked so they can be tracked over time • Photographic monitoring point established • First documented at the Monument in the early 1980’s

4. 1995 • monitoring continues as part of the National Park Services Long Term Ecological Monitoring Program • all flowering orchids marked to be tracked over time • record number of flowering orchids, height of flowering plants, number of inflorescence and buds counted • plants mapped using a total station or GPS unit • RAWS weather station placed near orchids in 1995 to collect daily temperatures, precipitation, wind speed and direction, and soil moisture probes

5. Prescribed Fire Management • burn no later then the first week of May • how to optimize the control of invasive species • research question of what impact does an early spring burn have on the flowering for the year • what about fall burns? • how long between burns? • Is it okay to burn in drought years?

6. Exotics and encroachment of woody species • smooth brome, reed canary grass, buckthorn, sweet clovers, Canada thistle • Native woody species such as wild plum, choke cherry, willows species; how often should we manually remove these species?

7. Hydrology • concerns with changes in Pipestone Creek’s hydrology • does pumping quarries impact the orchids (pumping started in the early 1970’s) • 1994 report stated that the disturbed hydrology is unlikely affecting the orchids now. The population reproduces by seeds so it has probably adapted to the hydrologic changes. • 1994 NPS report identified that a soil moisture strategy needs to be set up and remain a priority. Soil moisture is believed to be a primary factor influencing the orchid population.

8. Number of flowering orchids by year and date of previous fire, 1993-2000 * March precipitation missing

9. Total Reproductive Output: annually map distribution of flowering plants, measure plant height and count the number of flowers/buds.

10. Survivorship of ‘94 and ‘95 Flowering Individuals (56 flowering plants total) 3 - 16 dormancy events witnessed - 27% of individuals exhibited dormancy - average dormancy duration = 1.43 years (range from 1 to 3)

11. The Orchid Puzzle for Pipestone Objective: To assess changes in the population of orchids in relation to management actions and weather. Status of Non-Flowering Individuals. Number of Flowering Individuals, Total Reproductive Output Correlation with Management and Weather. Undetermined Longevity of Flowering Individuals

12. Context for Monitoring Non-flowering Individuals - The population at Pipestone is small, highly variable, and patchily distributed. Consequently, the population is highly susceptible to trampling. - Resources of the program preclude a demographic monitoring approach.

13. Adaptive Sampling: sampling designs in which the procedure for selecting sites or units to be included in the sample may depend on values of the variable of interest observed during the survey Thompson, Steven. 1992. Adaptive Sampling. John Wiley & Sons, INC. New York.

14. growing season weather insect activity pollination predation dispersal Seed bank formation of floral primordium soil disturbance germination reproduction dormant plants mature plants underground saprophyte animal activity growth & survival soil moisture mycorrhizal fungus symbiosis exotic species resource/nutrient availability plant community composition & structure hydrologic changes previous year precipitation prescribed fire fragmentation