nerveless or essentially so, substipitate, yellowish- 

 green, rounded and abruptly short beaked at the apex, the 

 beak brownish-red, . 5 mm long, emarginate or shallowly 

 bidentate; achenes obovoid, 2 X 1.35 mm, trigonous with 

 concave sides, sessile, granular, abruptly apiculate. 



3. Diagnostic characters (Hermann 1970): 



3 spikes, the terminal one with staminate flowers, if 



present, only at the apex, 

 scales longer than their perigynia 

 perigynia glabrous, with very short beaks 

 achenes triangular in cross section, style jointed to 



achene, with 3 stigmas 



B. GEOGRAPHIC DISTRIBUTION 



1. Range of the subspecies: Narrowly endemic in eastern Idaho 

 and western Montana (Murray 1969) , with one of the most 

 globally restricted distributions of the taxa surveyed in the 

 Tendoy Mountains. Though it is called "Idaho sedge", there 

 are no recent records in Idaho and it has not been well- 

 studied (Mosely pers. commun.). 



2. Montana distribution: previously known from three sites in 

 Silver Bow County and four sites in Beaverhead County, 

 including the Tendoy Mountains and Centennial Valley. 



3. Occurrences in the study area: Four new populations were 

 found, two in the upper Muddy Creek basin and two near the 

 confluence of Nicholia and Big Sheep Creeks. 



C. HABITAT 



Carex parryana ssp. idahoa occurs in moist alkaline meadows, 

 often along streams. These productive bottomlands are 

 dominated by graminoids {Deschampsia caespitosa, Juncus 

 balticus, Carex praegracilis) with or without shrubby 

 cinquefoil {Potentilla fruticosa) . Additional associates 

 include Aster occidentalis, Crepis runciniata, Agropyron 

 caninum, Potentilla anserina, Potentilla gracilis, Antennaria 

 microphylla, and Valeriana edule. The soils are silty and 

 calcareous. These habitats are often heavily grazed and 

 trampled by cattle. 



D. POPULATION BIOLOGY 



The populations are relatively small, ranging in numbers from 

 less than 50 to 500 estimated plants, and covering usually 1 

 or 2 acres. The largest population covers about 10 acres. In 

 early July the plants were in an early fruiting stage. 



E. MANAGEMENT CONSIDERATIONS 



C. parryana spp. idahoa is rare throughout its range in 

 Montana and Idaho. Nearly all of the known populations are 

 small and local and many are in apparent decline under the 



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