Alpinum: Answers to key questions in Rushes, Bulrushes & Pondweeds plus the remaining Monocots of Saskatchewan by V. L. Harms, A. L. Leighton, and M. A. Vetter leading to this species. The answers are in the order you would normally work through the key. 

	Culms trigonous with angles scabrous at least distally.  NOT [Culms terete with surface smooth (not scabrous).]
	Scales 15 - 20+ per spikelet; spikelets 5.4 - 8 mm long; bristles bright white, smooth, flattened, much longer than achenes; leaf blades 6 - 9 mm long.  NOT [Scales 3 - 6 per spikelet; spikelets 3.4 - 5.3 mm long; bristles pale brown, scabrous, terete, equaling or shorter than achenes; leaf blades (6) 15 - 250 mm long.]

Trichophorum: Answers to key questions in Rushes, Bulrushes & Pondweeds plus the remaining Monocots of Saskatchewan by V. L. Harms, A. L. Leighton, and M. A. Vetter leading to this genus. The answers are in the order you would normally work through the key. 

	Flowers and achenes naked in the axils of scales, not enclosed in a sac; flowers usually perfect (sometimes some flowers imperfect in Cyperus, Rhynchospora and Cladium).  NOT [Flowers and achenes enclosed in a sac (perigynium) borne in the axils of scales; flowers imperfect.]
	Perianth bristles absent or up to 6 per flower; if more than 6, then only somewhat longer than the achenes.  NOT [Perianth bristles usually more than 10 per flower, much longer than the achenes, conspicuously elongated to over 10 mm long in fruit stage and usually obscuring most scales in spikelets.]
	Inflorescence not a solitary, terminal spike; if solitary, terminal and spike-like, then inflorescence +/- terete.  NOT [Inflorescence a compressed, solitary, terminal spike bearing few-flowered spikelets attached in 2 rows.]
	Inflorescence a solitary terminal spikelet; inflorescence bracts absent or up to 8 mm long and only slightly longer than the spikelet; achenes usually <= 2 mm long (up to 2.3 mm in Eleocharis quinqueflora).  NOT [Inflorescence usually with > 1 spikelet; if only 1 spikelet present, then inflorescence bract usually 10 - 200 mm long (but as short as 7 mm in Schoenoplectus subterminalis) and achenes 2 - 3.5 mm long.]
	Leaf sheaths with short to long blades; inflorescence bracts present (may be absent at maturity because deciduous but will leave a scar) up to 8 mm long and only slightly longer than spikelets; scales 3 - 20+ per spikelet; achenes lacking a tubercle but sometimes beaked.  NOT [Leaf sheaths lacking blades; inflorescence bracts absent (subproximal and proximal scales, especially those lacking flowers, might be mistaken for very short bracts); scales 3 - 500 per spikelet; achenes usually bearing a clearly differentiated tubercle (but see Eleocharis quinqueflora and E. coloradoensis).]

Cyperaceae: Answers to key questions in Budd's Flora leading to this family. 

	plants not aquatic, or if growing in water, most of the plant emersed; NOT [plants aquatic, floating or submerged, with floating leaves or emersed inflorescence]
	culms usually solid; NOT culms usually hollow]
	leaves three-ranked; NOT [leaves two-ranked]
	inflorescence NOT [a dense, single, cylindrical spike 8-15 cm long, 1-2.5 cm thick],  if a single spike, less than 1 cm thick
	flowers not in globular heads; NOT [flowers in globular heads, the upper ones staminate, the lower ones pistillate]
	flowers solitary in the axil of a single bract (scale); NOT [flowers enclosed in two-ranked bracts with the lowest (glumes) empty]
	perianth absent or inconspicuous, not in two whorls; NOT [perianth present, conspicuous, in two whorls of 3 segments each, often brightly colored]
	perianth reduced to bristles or scales or lacking; NOT [perianth reduced to minute lodicules or lacking]