Dudleyi: 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. 

	Tepals subtended by a pair of floral bracteoles immediately below the flower; flowers borne singly in the inflorescence either +/- evenly distributed or +/- grouped in loose clusters (not in tight clusters, and if grouped in clusters individual flowers and paired floral bracteoles are still visible and not so tightly crowded such that individual flowers cannot be fairly easily identified); leaf blades, if present, not septate.  NOT [Tepals not subtended by a pair of bracteoles; flowers borne in tight clusters of 2 -100 (sometimes 1-flowered in Juncus stygius var. americanus), these clusters (glomerules) subtended by small bracts; leaf  blades septate (in most species) or not.]
	Inflorescences terminal and appearing terminal; primary bracts not appearing as terete extensions of the culms, leaf-like, erect-ascending; cataphylls and/or basal leaves present, cauline leaves present or absent; blades +/- flat or +/- canaliculate or +/- semi-terete; plants annual or perennial, culms loosely to densely cespitose.  NOT [Inflorescences terminal but appearing lateral; primary bracts appearing as an extension of the culms, terete, erect; cataphylls present, with truncate to acute tips or tipped with awns short or rarely to 200 mm long; basal and cauline leaves absent; plants perennial, culms usually well-spaced (some culms may be closely-spaced but are not cespitose) usually along unbranched or sparingly-branched elongate rhizomes.]
	Plants perennial, rhizomes present (but may be very short); inflorescences less than ca. one-eight total height of plant.  NOT [Plants annual, rhizomes absent; inflorescences at least one-third to two-thirds total height of plant.]
	Culms usually terete (if slightly compressed as in J. tenuis, then sepals >= 2.8 mm long); sheaths +/- loose; tepals usually >= 2.3 mm long; capsules usually 2.5 mm long or longer (may be as short as 1.7 mm long in J. dudleyi), usually included or +/- equal to perianth (exserted in J. vaseyi and may be slightly exserted in J. interior, but then capsules are at least 3 mm long); native species.  NOT [Culms slightly compressed to +/- terete; sheaths +/- tight; tepals usually 1.5 - 2 mm long but up to 2.8 mm; capsules 2.1 - 2.5 (3.5) mm long, long-exserted; introduced species recorded only from a disturbed roadside in Regina.]
	Leaf blades +/- flat to +/- canaliculate; seeds shorter and with short apicula.  NOT [Leaf blades subterete to +/- canaliculate; auricles 0.2 - 0.4 (0.6) mm long, scarious or rarely +/- leathery; sepals (2.3) 3.3 - 4.4 mm long, petals (2.3) 2.8 - 4.3 mm long; capsules distinctly 3-locular, (3.3) 3.8 - 4.7 (6) mm long, exserted, ellipsoidal; seeds 1 - 1.7 (2) mm long including the apicula, fusiform, with 2 conspicuous, narrow and white apicula each 0.2 - 0.5 (0.7) mm long and half to one-third of total seed length; a common species of boreal forest regions.]
	Culms usually 0.8 mm wide or wider ((0.4) 0.5 - 1 mm wide in J. interior); tepals greenish becoming stramineous, edges may be darker; tepals margins membranous; capsules 1-locular to pseudo-3-locular (septa extending nearly to the center in J. interior); inflorescences 10-70 (90) mm long, generally longer than those of J. confusus; primary bracts leaf-like but not filiform (may be narrow to nearly filiform in J. dudleyi); not limited to the Cypress Hills and mixed-grass prairie region (except Juncus interior, which is recorded in mixed-grass prairie region only).  NOT [Culms (0.3) 0.5 - 0.6 (0.8) mm wide; tepals greenish becoming pale brown with darker-brown edges that appear like 2 lines running the length of the tepals; tepal margins hyaline; capsules distinctly 3-locular; inflorescences 8 - 20 (25) mm long; primary bracts leaf-like and +/- filiform (0.4 - 0.5 mm wide), usually much longer than inflorescences; a relatively rare species of the Cypress Hills and mixed-grass prairie region.]
	Culms terete; leaf blades 50 - 300 mm long; auricles 0.2 - 0.4 (0.6) mm long, scarious or leathery to cartilaginous; not limited to boreal forest regions.  NOT [Culms terete to slightly compressed; leaf blades 30 - 120 (200) mm long; auricles (1) 1.5 - 5 (6) mm long, membranous; a common species of boreal forest regions.]
	Auricles leathery to cartilaginous, yellowish; sepals (3.7) 4 - 5 (5.4) mm long, petals 3.4 - 4.8 (5.2) mm long; anthers (0.5) 0.7 - 0.9 mm long; capsules (1.7) 2.5 - 3.6 (4.2) mm long with ca. 0.2 mm long mucros, included; a very common species throughout the province.  NOT [Auricles scarious, whitish to pale brown to purplish-tinged; sepals 3 - 4.2 (4.5) mm long, petals 3 - 4.2 (4.5) mm long; anthers 0.4 - 0.6 (0.8) mm long; capsules 3 - 4 (4.5) mm long with 0.1 mm long mucros, equal to perianth to slightly exserted; uncommon in the mixed-grass prairie region.]

Juncus: 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. 

Leaves various, glabrous; sheaths open, often with margins projected as auricles; flowers with or without a pair of floral bracteoles immediately below the tepals; capsules 1- or 3-locular (or pseudo- or incompletely-3-locular), placentation axile or parietal; seeds many.  NOT [Leaves +/- flat and grass-like, sparsely to densely ciliate; sheaths closed (or sometimes partially splitting later), auricles absent; flowers with 1 - 2 floral bracteoles immediately below the tepals; capsules 1-locular, placentation basal; seeds 3.]

Juncaceae: 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]
	flowers not in globular heads; NOT [flowers in globular heads, the upper ones staminate, the lower ones pistillate]
	flowers in branched inflorescences; NOT [inflorescence a dense, single, cylindrical spike 8-15 cm long, 1-2.5 cm thick], NOT [flowers in spike-like racemes]
	perianth in two whorls, each of three segments
	perianth segments inconspicuous and scale-like; NOT [perianth segments conspicuous and often brightly colored], NOT [perianth of greenish sepals and petals]