Table 3. Comparison of soil parameters at Spiranthes diluvialis sites 



Soils at the Montana sites are typically light in color, chrome and hue (most 

 are 2.5Y 6/2), moderately alkaline (pH 7.6-8.07), and are all loamy (loam, 

 sandy loam, or silt loam) with exception of one exceptionally well-developed 

 marl deposit area (part of EO#004). It may have had so much soluble calcium 

 carbonate accumulation ("bog lime") that there was too little sediment to 

 place it in a textural class. Sand otherwise makes up the majority of the 

 sediment in all samples except in one sample classified as a silt loam 

 (EO#005). The marl sample and two other soil samples have 20% or more 

 organic content which is comparable to productive farmlands but which, if 

 composed of undecayed material, potentially classifies them as peat or 

 histosols. Coarse alluvial cobble was foimd below the soil horizon at each of 

 the five sites. In some cases the soil profile was thinner than the 10 cm depth 

 of the soil sample above the loose cobble, in which case the loose, smoothly- 

 rounded cobbles were excluded from textural classification. 



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