|  | Prairea:
    Answers to key questions in Sedges (Carex) of Saskatchewan, Fascicle 3,
    Flora of Saskatchewan by Anna Leighton leading to this species. The
    answers are in the order you would normally work through the key. 
     
      |  | Stigmas 2;
        achenes lenticular. NOT [Stigmas 3; achenes three-sided, occasionally
        terete, though their shape may be concealed by flattened perigynia] |  |  | Spikes 2
        or more per culm, terminal and lateral; spike bracts present on lateral
        spikes; lowest spike bracts usually evident, often conspicuous, even in
        compact heads composed of densely bunched and indistinguishable spikes
        (except in  C. maritima,  C. chordorrhiza and  C.
        microptera).  NOT
        [Spikes 1 per culm, terminal; spike bracts absent] |  |  | Individual
        spikes distinguishable in an open inflorescence, or indistinguishable in
        a compact head; spikes in any one inflorescence alike in appearance due
        to their similar composition (i.e. all are gynecandrous, androgynous,
        pistillate or staminate), sessile.  NOT [Individual spikes
        distinguishable in an open inflorescence (densely bunched in  C.
        bicolor); spikes in any one inflorescence either markedly different in
        appearance (with terminal spike staminate and lateral spikes
        pistillate), or subtly different in appearance (with terminal spike
        gynecandrous and lateral spikes pistillate), sessile or stalked.] |  |  | Culms
        loosely to densely cespitose (occasionally mat-forming rather than in
        discrete clumps); rhizomes, if present, usually short with culms arising
        close together along them. NOT [Culms single, or a few together,
        well-spaced along conspicuous rhizomes or stolons.] |  |  | Spikes
        androgynous, (lateral spikes occasionally pistillate in  C. prairea); if
        heads have indistinguishable spikes, the heads are usually oblong to
        elongate in shape.  NOT [Spikes gynecandrous, (terminal spikes may
        be staminate in SK material of  C. mackenziei; pistillate or staminate
        spikes occur in Sect. Stellulatae, a group distinguished by spongy
        tissue filling lower one-third to one-half of the perigynium); if heads
        have indistinguishable spikes, the heads are usually +/- as wide as they
        are long and usually widest in middle or toward base.] |  |  | Spikes
        usually more numerous, mostly overlapping, and in some species
        indistinguishable in a simple or compound inflorescence; beak 0.3 mm
        long or longer.  NOT [Spikes 2-5, widely spaced along 1.5-3 cm of
        culm with only upper few clustered at tip; beak a tiny tube less than
        0.25 mm long.] |  |  | Inflorescence
        usually larger, if less than 2 cm long then leaves 2 mm wide or wider;
        culms in most species over 3 dm high.  NOT [Inflorescence small,
        0.7-1.5 (2) cm long and to 0.7 cm wide, compact with indistinguishable
        spikes; leaves 0.5-1 mm wide; culms (0.4) 0.6-2.6 (4) dm high.] |  |  | Perigynia
        body not translucent; lateral margins of perigynia not conspicuously
        green-margined except along beak in some species.  NOT [Perigynia
        body +/- translucent with brown achene showing through walls; lateral
        margins of perigynia green and conspicuous.] |  |  | Distal
        portion of culm 0.5-1 mm wide (to 2 mm wide in  C. vulpinoidea), firmly
        three-angled, not easily flattened; culm angles not winged.  NOT
        [Distal portion of culm 1.5-4 (7) mm wide, soft, easily flattened under
        pressure; culm angles with wide, flat wings.] |  |  | Leaves 3
        or 4 mm wide at most; dorsal (abaxial) surface of lower leaf sheaths not
        conspicuously green and white striped, if septate-nodulose then
        partitions between veins faint; plants more widely distributed. 
        NOT [Leaves 3-5 (8 fna) mm wide; dorsal (abaxial) surface of lower leaf
        sheaths conspicuously striped with longitudinal green veins against a
        white background and septate-nodulose with prominent partitions between
        veins; plants of moist, shady sites in southeastern SK.] |  |  | Only lower
        bracts clearly visible, these to a maximum length of 1.5 cm; leaves
        shorter than or equal to culms; pistillate scales acute, acuminate or
        occasionally mucronate, not awned; ventral strip neither rugose nor
        thickened at summit.  Section  Heleoglochin (C. prairea, C.
        diandra).  NOT [Bristle-like bracts visible throughout
        inflorescence, lower bracts 0.5-6 (13) cm long, often as long as or
        longer than inflorescence; leaves longer than culms; pistillate scales
        with awns 1-5 mm long; ventral strip rugose with thickened edge at
        summit.] |  |  | Summit of ventral strip a copper-colored band visible with the
        naked eye; perigynia straw-colored to brown at maturity, dark brown with
        age, often entirely covered by scales that mask their color and shape
        except for the long stigmas; inflorescence pale brown at maturity;
        spikes and panicle branches loosely and somewhat irregularly overlapping
        (lowest often separate, occasionally remote)  in an elongate head. 
        NOT [Summit of
        ventral strip whitish with red dots not forming a continuous visible
        band; perigynia pale to dark chestnut brown at maturity, almost black
        with age, somewhat longer than scales which may be short and translucent
        revealing brown potbellied perigynium bodies; inflorescence dark brown
        at maturity; spikes and panicle branches closely and regularly
        overlapping (lowest occasionally separate) in a cylindrical head.] |  |