Sphenopbolis obtusata var. major (Torr.) K. S. Erdman 



syn. Sphenopltolis intermedia (Rydb.) Rydb. 



SLENDER WEDGEGRASS 



Poaceae 



A. PRESENT LEGAL OR OTHER FORMAL STATUS 



1. FEDERAL STATUS 



a. U.S. FISH AND WILDLIFE SERVICE: None. 



b. U.S. FOREST SERVICE: None. 



2. STATE: G5T5 SH (historic in Montana). This study clears up taxonomic 

 confusion, documenting that the rare variety is not present on Custer National 

 Forest. 



B. DESCRIPTION 



1. GENERAL NONTECHNICAL DESCRIPTION: Slender wedgegrass is an 

 herbaceous annual or short-li\'ed perennial grass, with a slender nodding open 

 spike at the top of the 0.2-1 m (8-40 in.) stem (Figure 14). It is two-flowered 

 and the seeds drop with the glumes. The shape and difference in width of the 

 two glumes is distinctive, the large second one being very broad at the upper 

 end like the shape of a wedge, hence the common name. 



2. TECHNICAL DESCRIPTION: Culms erect in small tufts, 30-120 cm tall; 

 sheaths glabrous or pubescent; blades flat, often elongate, lax, mostly 2-6 mm 

 wide, sometimes wider, mostly scaberulous, occasional sparsely pilose; panicle 

 nodding, from rather dense to open, mostly 10 - 20 cm long, the branches 

 spikelet-bearing fi-om base; spikelets 3-4 mm long; second glume relatively 

 thin, acute or subacute, about 2.5 mm long; lemmas subacute, rarely 

 mucronate, smooth or rarely very minutely roughened, mostly 2.5-3 mm long 

 (Hitchcock 1971). 



3. LOCAL FIELD CHARACTERS: The rare variety, S. obtusata var. major is 

 synonymous with Sphenopbolis intermedia (Rydb.) Rydb as treated in Dom 

 (1984). It has a nodding and somewhat open inflorescence, in contrast to the 

 spike-like inflorescence of 5. obtusata var. obtusata. The second glume is over 

 3X as long than wide and not cucuUate; lower lemma is 1.9-3.1 mm long 

 (Great Plains Flora Association 1986). 



The different nomenclature used in taxonomic references may be a source of 

 confusion. Most floras recognize 5". obtusata as distinct from 5". intermedia 



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