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1 Keel of the lateral sepals shortly ciliate- scabrid (or sometimes entire in X. brevifolia, and then the bract tips purplish-tinged). |
2 Plants small, usually < 30 cm tall; principal leaves usually < 10 cm long; mature spikes < 1 cm long when mature. |
3 Leaves filiform, with expanded brownish lustrous bases, usually exceeding the sheath of the scape; [plants of s. AL and the FL Panhandle] |
3 Leaves linear, the bases not expanded, shorter than, equaling, or slightly exceeding the sheath of the scape; [plants collectively more widespread]. |
4 Keel of the lateral sepals straight to slightly curved, remotely ciliate or entire; spikes broadly ovoid to subglobose, the bracts loose, bicolored, the distal portions maroon or purplish and often with erose margins |
4 Keel of the lateral sepals strongly curved, densely ciliate; spikes lance-ovoid to ovoid, the bracts entire, not purple-tinged, and lacking erose borders. |
5 Plants perennial; leaves ascending, green with a distinct brown patch at the base; fruiting spikes ovoid, blunt, somewhat 2- edged from the strongly keeled outer bracts |
5 Plants annual; leaves flabellate arranged, spreading to recurved against the substrate, usually maroon; fruiting spikes often elongated and acute, not 2- edged |
2 Plants large, usually > 30 cm tall; principal leaves > 10 cm long; mature spikes > 1 cm long when mature. |
6 Leaves ascending, twisted, strongly grooved; spikes ovoid, the bracts and lateral sepals with a small tuft of short, reddish-brown hairs; bases of leaves abruptly expanded, pinkish or purplish (dark brown in age), the outermost leaves often scale-like, the plant base therefore appearing bulbous; [of the Mountains, Piedmont, and Coastal Plain] |
6 Leaves spreading, not twisted or only slightly so; spikes narrowly ovoid, ellipsoidal, or oblong; bracts and sepals without a small apical tuft of hairs; bases of leaves whitish, tan, pink, purplish, maroon, or dark brown, the outermost leaves not scale-like, the plant base not appearing bulbous; [typically of the Coastal Plain, rarely disjunct inland]. |
7 Seeds lustrous, translucent, broadly ovoid; spike pale brown or tan, the scales loosely imbricate; plant bases pinkish, purplish, or tan, with dark longitudinal striations on the inner leaf bases; leaves 3-20 mm wide; petal blades obovate, 6-7 mm long, opening in early morning, usually closing by mid-day |
7 Seeds farinose, dark brown ( X. stricta) or pale ( X. louisianica) at maturity, narrowly ellipsoid to ovoid; spike dark brown, the scales tightly imbricate; plant bases maroon, purplish, dark-brown, or reddish-brown; leaves 2-5 mm wide; petal blades triangular- cuneate, 3-5 mm long, opening at mid-day. |
8 Seeds pale when mature; plant bases maroon to maroon-brown, solitary or in small clumps; upper end of scape somewhat flattened, but not nearly as broad as the spike; spike narrowly ovoid to ellipsoid, slightly pointed |
8 Seeds dark brown when mature; plant bases dark maroon to dark brown, densely cespitose; upper end of the scape conspicuously flattened, almost as broad as the spike; spike oblong- cylindrical, obtuse |
1 Keel of the lateral sepals irregularly lacerate or fimbriate, or if entire then the bract tips not purplish. |
9 Leaves 0.5-2.0 (-2.5) mm wide, not twisted (or scarcely so); leaf bases expanded, lustrous, hard, tan to brown, neither bulbous nor deeply set in the substrate; spikes ovoid or ellipsoid, 4-15 mm long. |
10 Bract tips smooth- edged to denticulate, not curled away from the spike, the spike thus appearing smooth; staminodia beardless |
10 Bract tips ragged- lacerate, the tips curling away from the head, giving it a ragged appearance; staminodia bearded. |
11 Leaves linear, flattened in cross-section, 1.0-2.0 (-2.5) mm wide, with a pale, hardened margin; scape usually narrower than the leaf blades; [e. SC south to s. FL, west to s. MS] |
11 Leaves filiform, terete or elliptic in cross-section, 0.5-1.0 mm wide, without a paler, hardened margin; scape as broad as or broader than the leaf blades, usually less than twice the length of the longest leaves; [FL, perhaps elsewhere] |
9 Leaves (1.5-) 2.0-25 mm wide, strongly twisted to straight, the leaf bases either not expanded, lustrous, hard, and tan to brown, or, if so, then the base also either bulbous and/or deeply seated in the substrate; spikes narrowly lanceolate, ellipsoid, to broadly ovoid, 4-40 mm long. |
12 Keel of the lateral sepals long- fimbriate toward its apex, the fimbriate tip conspicuously exserted from the subtending bract (sometimes eroded and less conspicuous on older spikes). |
13 Leaves strongly twisted, 2-5 mm wide; leaf bases hardened, swollen, bulbous, dark lustrous brown; scape ridges smooth; petal blades white or yellow; [of moist to dry pinelands] |
13 Leaves not twisted or slightly twisted, 3-25 mm wide; leaf bases either soft, not swollen, not bulbous, and pale green ( X. fimbriata) or somewhat hardened and bulbous, deep red ( X. panacea); scape ridges strongly scabrous or smooth; petal blades yellow; [of aquatic to very wet peaty, mucky, or sandy ponds, marshes, or other wetlands]. |
14 Leaves 5-25 mm wide; scape ridges well-developed, strongly scabrous; flowers open 1:00-3:00 p.m. EDT; [widespread] |
14 Leaves 3-5 (-8) mm wide; scape ridges poorly-developed, smooth; flowers open 11:30-4:00 p.m. EDT; [ endemic to Wakulla County, FL] |
12 Keel of the lateral sepals lacerate, or if very shortly fimbriate, then not conspicuously exserted from the subtending bract. |
15 Lateral sepals longer than and exserted from the subtending bracts (or if nearly hidden, the plants strongly rhizomatous). |
16 Spikes 4-8 mm long; leaves 4-15 cm long; [in our area, ne. PA and n. NJ, and northwards] |
16 Spikes 10-32 mm long; leaves 6-50 (-60) cm long; [in our areas, s. NJ, and southwards, and also in coastal and nearly coastal New England]. |
17 Leaf blades 5-15 mm wide, (20-) 30-50 (-60) cm long; spikes 10-20 (-25) mm long; seeds (0.6-) 0.7 (-0.8) mm long; [more widespread in our area] |
17 Leaf blades 1-2 (-3) mm wide, 6-30 cm long; spikes 10-16 mm OR 20-32 mm long; seeds 0.4-0.6 mm long; [of FL and s. AL]. |
18 Plants perennial, mat-forming by long, scaly rhizomes; spikes 20-32 mm long; petal blades deeply lacerate at tip, the lobes 1.0-1.5 mm long; seeds with obscure alveolae; [ endemic to peninsular FL] |
18 Plants annual, cespitose; spikes 10-16 mm long; petal blades slightly erose or serrate at tip; seeds with regular, rectangular alveolae; [ endemic to Panhandle FL and s. AL] |
15 Lateral sepals shorter than the subtending bracts, and therefore hidden (except when the spikes open to shed seeds) AND plants never rhizomatous. |
19 Scapes flexuous, usually spirally twisted; upper portion of leaf blades conspicuously twisted; plant bases pinkish, purplish, or dark brown, bulbous or deeply set in the substrate. |
20 Seeds opaque; seed surfaces slightly to densely farinose; scape 1.5-8 (-8.5) dm tall; [ calcareous habitats of FL, AL, and TN]. |
21 Plant forming a rather dense tuft; spike diverging from the scape at a 10-20° angle; [of ne. FL southward] |
21 Plant solitary or in small tufts; spike vertical. |
22 Scape 3-7 dm tall; leaf sheaths and blade surfaces mostly smooth or slightly rough- papillose only along the keels and edges; scapes with 5-7 sharply angled ridges, densely papillose on the ridges and in the grooves; stem base with or without short- ascending rhizomes |
22 Scape 1.5-4 dm tall; leaf sheaths and blade surfaces rough- papillose on the surfaces and along the keels and edges; scapes with 2 ridges, somewhat flattened and winglike upwards, slightly papillose on the ridges only (the grooves smooth); stem base lacking rhizomes |
20 Seeds translucent; seed surfaces not farinose; scape 2-11 dm tall, but usually > 5 dm tall; [collectively widespread in acidic habitats of the Coastal Plain (and rarely Piedmont), NJ south to s. FL, west to e. TX)]. |
23 Base of plant deeply set in the substrate, without distinct outer scale leaves; leaf bases not noticeably expanded, the plant base therefore not bulbous; leaves smooth, 2-4 mm wide; petal blades ca. 3 mm long |
23 Base of plant shallowly set on the substrate, often with short, black outer scale leaves; leaf bases noticeably expanded, the plant base therefore appearing bulbous; leaves either smooth and 5-10 mm wide, or scabrous and 2-10 mm wide; petal blades ca. 5 mm long. |
24 Leaf and scape surfaces smooth (or scabrous only along margins and ridges); petal blades obovate, white or yellow; seeds ovoid or ellipsoid, 0.5-0.6 mm long |
24 Leaf and scape surfaces prominently papillose or tuberculate- scabrid; petal blades suborbicular, yellow; seeds narrowly ovoid or narrowly ellipsoidal, ca. 1.0 mm long |
19 Scapes usually not flexuous, usually not spirally twisted; upper portion of leaf blades not conspicuously twisted; plant bases variously colored, flabellate or equitant and set at ground level. |
25 Summit of the scape distinctly flattened and broad relative to the spike; scape ridges 2-3, the 2 most prominent comprising the flattened edge of the scape. |
26 Fruiting spikes mostly 5.5-7.5 mm long; spikes subtended by 2 linear- lanceolate, leaf-like bracts, green with scarious margins; [known only from Long Island, NY] |
26 Fruiting spikes mostly 8-25 mm long; spikes not subtended by leaf-like bracts; [collectively widespread]. |
27 The 2 principal scape ridges noticeably and abruptly flattened and winglike below the spike, their combined width (on fresh material) broader than the scape proper; fruiting spikes mostly 8-15 mm long; seeds 0.4-0.6 mm long, translucent, ovoid or ellipsoidal, about 1.5× as long as wide, with lines of very fine papillae, not farinose; petals yellow |
27 The 2 principal scape ridges not abruptly flattened and winglike below the spike, their combined width < the scape proper, which is itself flattened (narrowly elliptic in cross-section); fruiting spikes mostly (10-) 20-25 mm long; seeds 0.8-1.0 mm long, dark when ripe, fusiform to narrowly elliptic, 2-3× as long as wide, with lines of very fine papillae, these however obscured by a farinose covering; petals yellow or white |
25 Summit of the scape nearly terete or somewhat flattened, much narrower than the spike; scape ridges several (usually > 3), at least on the mid to lower portion of the scape. |
28 Seeds farinose, very dark; surfaces of leaves tuberculate- scabrid, the leaves strongly ascending, linear, generally > 10 cm long; leaves generally dull-colored. |
29 Mature spikes ovoid, sharply acute; plants solitary or in small clumps; leaves 10-30 (-50) cm long, 1.5-6.0 mm wide, dark maroon or purplish at the base |
29 Mature spikes ovoid to ellipsoid, acute to obtuse; plants typically in large dense tufts; leaves 20-50 cm long, 3-12 mm wide, the older ones with dark-brown to gray bases, the younger with tan bases |
28 Seeds translucent, not farinose; surfaces of leaves smooth (or sparsely tuberculate- scabrid in X. curtissii, which also has leaves linear-curvate and generally < 10 cm long); leaves generally a bright yellowish-green above the base. |
30 Leaves spreading- recurved to erect, 3-13 cm long, 1-4.5 mm wide; scapes at mid-length 0.4-0.6 (-0.7) mm wide; mature spikes 3-7 (-12) mm long; fertile bracts 3-5 mm long; leaf bases various; old flowers fugacious, not persisting on spikes; seeds 0.3-0.5 mm long. |
30 Leaves ascending to erect, 5-60 cm long, 2-5 (-15) mm wide; scapes at mid-length (0.5-) 1.0-1.5 (-2.0) mm wide; mature spikes 7-15 (-25) mm long; fertile bracts 5-7 mm long; leaf bases tan to brown; old flowers often persisting on spikes, drying blackish; seeds 0.4-0.5 mm long |