D. POPULATION BIOLOGY 



The population which was surveyed was estimated to consist of 

 more than 100 plants but was not thoroughly surveyed. Plants 

 were in a flower bud stage in early June. 



E. MANAGEMENT CONSIDERATIONS 



S. capitata is common on limestone outcrops around Clark 

 Canyon Reservoir. It is also abundant on the south side of 

 the Pryor Mountains, where 16 populations were discovered in 

 1991 (Lesica and Achuff 1992). The limestone outcrop habitat 

 is not generally threatened. This species is too common to be 

 considered further for BLM sensitive species designation but 

 is appropriately placed in the state limited distribution 

 category. 



Stctnleya viridiflora Nutt. 

 Green prince's plume 



A. DESCRIPTION 



1. General description: This is a large, showy member of the 

 Brassicaceae (the mustard family) . The blueish green leaves 

 lack hairs and petioles. The small flowers are borne in a 

 long raceme. There are 4 green sepals, 4 yellow petals, 6 

 stamens and a single ovary. The fruit is a silique (long, 

 splitting along its length, with 2 chambers separated by a 

 membrane) with a stalk above the attachment of the perianth 

 parts. 



2. Diagnostic characters: The long raceme of showy yellow 

 flowers is very conspicuous in the field and gives the genus 

 its common name, prince's plume. The genus is distinguished 

 from other mustards in Montana by having a stipitate silique. 

 S. viridiflora is separated from other Montana species of 

 Stanleya by having auriculate, sessile (rather than petiolate) 

 leaves. 



B. GEOGRAPHIC DISTRIBUTION 



1. Species range: Welsh et al. (1987) describe the range as 

 "Idaho and Wyoming to Nevada and Oregon." It is also found in 

 southwestern Montana. 



2. Montana distribution: Nine previous records from Beaverhead 

 and Madison Counties. 



3. Occurrences in the study area: There are now 9 new 

 populations known on BLM lands and another on state land in 

 the foothills and canyons of the Tendoy Range. 



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