according to A. Reznicek (Lesica pers. commun.); the determination is in 

 progress. This same unknown species has been collected in the area of 

 Spiranthes diluvialis in Gallatin and Madison counties as part of the study 

 and submitted to Reznicek. 



Finally, the exotic meadow fescue {Festuca elatior; Festuca arundinacea) 

 was often found in wetland margin and meadow. It occurred sporadically as 

 an adventive species rather than in abimdance as a planted species. 



6. Dependence on dynamic aspects of biotic associations and ecosystem 

 features: The plants associations are made up of long-lived perennials, but 

 their vigor and flowering activity from year-to-year are variable with climate 

 and with livestock grazing. The wetland microhabitats are intrinsically 

 dynamic with changes in water availability and aerobic/anaerobic conditions. 



7. Other endangered, threatened, rare, or vulnerable species occurring in 

 habitat of this taxon: Two peripheral Montana Species of Special Concern 

 were often found in association with Spiranthes diluvialis in Montana: 

 Castilleja exilis fannual paintbrush; G5 S2)), a Great Basin species, and 

 Primula incana (mealy primrose; G4G5 S2), a boreal species. Relocation of 

 collection sites for these two species was attempted as part of the survey, 

 including historic records, representing a visit to most of the collection areas 

 in southwestern Montana. The Castilleja exilis is present at the majority of 

 the wetland sites for Spiranthes diluvialis, but it is not restricted to these 

 wetland settings. Prior to Peter Lesica's collection of it in 1994, it was 

 known only from four historic records, the most recent of which was 1906. 

 This species has a broader ecological amplitude and geographic distribution 

 than Spiranthes diluvialis in Montana. New county records or relocated 

 historic records for it were documented as part of this study in Beaverhead, 

 Broadwater, Deerlodge, Gallatin, Granite, Madison, and Silverbow counties, 

 in addition to Jefferson County. 



The Primula incana is a boreal species which is also present at the majority 

 of Spiranthes diluvialis occurrences, corresponding with the sites having the 

 greates amount of calcium carbonate deposition. It has a broader distribution 

 in Montana than Spiranthes diluvialis, but it is more restricted in its habitat to 

 soils that remain saturated throughout the growing season, and which are 

 consistently high in calcium carbonate. New county records or relocated 

 historic records for it were documented as part of this study in Beaverhead, 

 Broadwater, Deer Lodge, Gallatin, and Silverbow counties, in addition to 

 Jefferson County. 



In addition, Eleocharis rostellata (beaked spikerush; G5 S2) has been 

 identified in the vicinity of Spiranthes diluvialis occurrences, and is suspected 



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