The only place where it was found under late-summer grazing was in 

 a lightly-stocked bull pasture. The two largest species' populations at 

 the time of listing had a history of winter-grazing, more notable for 

 their intact vegetation condition than for signs of grazing (U.S. Fish 

 and Wildlife Service 1992). 



There were no mowing activities observed in its habitat because the 

 setting remains wet and is oriented in winding narrow bands. 

 Mowing takes place in some of the adjoining uplands, and those 

 meandered wetlands surrounded by hayland were particularly choked 

 with exotic grasses or cattails compared to nearby sites supporting 

 Spiranthes diluvialis, . Mowing may have historically taken place 

 within the few occurrences in swale wetlands when machinery was 

 smaller and lighter, but there were no signs of it. 



Irrigation and water diversions are common in the area, and some sites 

 adjoin active or plugged man-made ditches. They are part of a system 

 for providing water to agricultural lands that are mainly higher up in 

 the landscape. Some of the natural meandered wetlands provide 

 overflow for irrigation water. The net affect on Spiranthes diluvialis 

 habitat appears to be the raising of the water levels because filtration 

 takes place from the ditch or natural channel out to the surroundings. 

 The occurrence that seems most affected by irrigation water discharge 

 is also the most extensive occurrence (#004). It is interesting to note 

 that one terrace swale area formerly innundated by ditch seepage 

 (owner pers. commxm.) now has the ditch plugged and a large 

 numbers of Spiranthes diluvialis (#005) in the swale below. Some 

 road ditches are hydrologically tied to the meandered wetlands, 

 though there was not evidence that they contribute to the dewatering 

 or innundation of the natural wetland habitat. 



Roads and railroads lace the valleybottoms in which the species 

 occurs, and several occurrences are partially or wholly within 0. 1 mile 

 of county road. This proximity is not a management conflict, except 

 insofar as the roads become corridors for the spread of noxious weeds. 

 One occurrence is restricted to a roadside right-of-way but the present 

 level of use by dirt-bikers and horse-back riders traveling along the 

 road is light or absent and damage was not found among plants. 



b. Related taxa: There have been many management response studies 

 and literature reviews pertaining to orchid species and their response 

 to various land management practices. The most closely-related 

 species and species' habitat for comparison with Spiranthes diluvialis 

 is S. magnicamporum. A literature review of its management 



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