The ten occurrences may have historically represented five 

 metapopulations. In any case, they represent five areas where the 

 associated soil series occurs. They are all greater than 2 miles fi-om 

 one another and do not have continuous habitat, so they are treated as 

 separate occurrences. 



2. Populations known or assumed extirpated, 

 a. Montana: None. 



3. Historically known populations where current status is not known: 

 a. Montana: Not applicable. 



4. Locations not yet investigated believed likely to support additional 

 natural populations. This report represents the results of systematic survey 

 across eight counties; roughly circumscribing species' distribution in western 

 Montana, doubling the number of occurrences since the interim report 

 (Heidel 1 997), adding two new counties of distribution, and diminishing the 

 likelihood of occurrences in other western Montana counties and along other 

 rivers. Landscapes in southwestern Montana with meandered wetland 

 complexes , the four soils series, and collection records of the associated 

 species have been evaluated to determine presence/absence. Compilation of 

 soils information is needed to critique completeness. Nor is the search for 

 occurrences within each setting to be considered exhaustive due to access and 

 time constraints, but the distribution is demarcated. The upstream extent of 

 the species on the Ruby River above Alder was treated in incomplete surveys, 

 the upstream extent on the Beaverhead River immediately upstream ft-om 

 Dillon was not investigated, nor were all associated species collection sites in 

 southern Beaverhead County evaluated (i.e.. Primula incana in the well- 

 studied settings of Carex parryana ssp. idahoa.) 



There have been no surveys for it in eastern Montana. There is inadequate 

 background information for determining the appropriateness of such 

 investigation. It has been collected in the Great Plains of southeastern 

 Wyoming in a watershed that does not extend into Montana. There is one 

 Spiranthes specimen fi-om Sheridan County in the extreme northeastern 

 comer of Montana that represents a range extension for the Spiranthes genus 

 in Montana. Though it is unlikely to be S. diluvialis, it deserves special 

 mention. It was collected in 1923 and deposited at the Missouri Botanical 

 Gardens (Sheviak pers. commun.). The material is not useable for definitive 

 identification, and there are no other known collections of ladies '-tresses 

 fi-om eastern Montana, though both parent species are extant in highly 

 restricted peatland settings of North Dakota to the east. 



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