Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.
1 Receptacles with paleae or bristles. |
..2 Pappus lacking or of scales or awns. |
|
......4 Involucre of dentate or fimbriate phyllaries |
......4 Involucre of the pistillate heads a bur with hooked prickles |
|
........5 Phyllaries dentate or fimbriate |
........5 Phyllaries entire |
|
..........6 Phyllaries fimbriate, dentate, or spiny; leaves often prickly or spiny |
..........6 Phyllaries entire, leaves not prickly or spiny. |
............ 7 Basal leaves 1-5 mm wide; outer florets pistillate |
............ 7 Basal leaves > 5 mm wide (except in Liatris pseudoliatris); florets all perfect. |
............ ..8 Phyllaries hooked at tip; heads forming burs at maturity |
............ ..8 Phyllaries not hooked at tip; heads not forming burs at maturity. |
............ ....9 Heads larger, the involucre 6-15 mm high, with 15-40 phyllaries; leaves with conspicuous (at least at 10× magnification) resin dots |
............ ....9 Heads small, the involucre 3.5-6 mm high, with 5-12 phyllaries; leaves without shining punctate glands (except punctate-glandular in Litrisa, of the FL peninsula). |
............ ......10 Stem with punctate glands; peduncles punctate-glandular and also hirsutulous; pappus bristles in 2 series; [of FL peninsula] |
............ ......10 Stem eglandular, glabrous or spreading-hirsute; peduncles glabrous or stipitate-glandular; pappus bristles in 1 series; [widespread in the Coastal Plain] |
|
............ ........11 Pappus lacking or of scales or awns. |
............ ..........12 Disk florets blue or purple. |
............ ............ 13 Heads few-flowered, aggregated into secondary heads with leafy bracts |
............ ............ 13 Heads many-flowered, not aggregated into secondary heads |
............ ..........12 Disk florets yellow to yellowish green or reddish to reddish brown. |
............ ............ ..14 Cypselas winged and spined; heads sessile in the branch forks |
............ ............ ..14 Cypselas not winged and spined; heads not sessile in the branch forks. |
............ ............ ....15 Inflorescence elongate, paniculiform, spiciform, or racemiform |
............ ............ ....15 Inflorescence a flat-topped corymb, or heads solitary. |
............ ............ ......16 Receptacle strongly convex and pointed; plants pineapple-scented |
............ ............ ......16 Receptacle flat to convex; plants scented, but not of pineapple |
............ ........11 Pappus of barbellate or plumose bristles. |
............ ............ ........17 Heads yellow. |
............ ............ ..........18 Perennial; leaves remotely toothed to entire; [of shale barrens] |
............ ............ ..........18 Annual; leaves irregularly toothed to pinnatifid; [weed of disturbed soil] |
............ ............ ........17 Heads white, whitish, pink, purple, red, |
............ ............ ............ 19 Florets all perfect. |
............ ............ ............ ..20 Larger leaves hastate; heads whitish |
............ ............ ............ ..20 Leaves not hastate; heads whitish to red or pink to violet or deep purple. |
............ ............ ............ ....21 Phyllaries in essentially one series; leaves palmately veined, ovate to reniform |
............ ............ ............ ....21 Phyllaries in several series; leaves variously veined, linear to broadly ovate. |
............ ............ ............ ......22 Heads white or whitish; [of uplands] |
............ ............ ............ ......22 Heads pink to red or violet to deep purple or, rarely, white; [of uplands or wetlands]. |
............ ............ ............ ........23 Pappus bristles of one length |
............ ............ ............ ........23 Pappus double with inner bristles long and the outer very short |
............ ............ ............ 19 Some or all florets pistillate. |
............ ............ ............ ..........24 Leaves not white-woolly. |
............ ............ ............ ............ 25 Phyllaries in essentially one series; fresh plants not strongly scented |
............ ............ ............ ............ 25 Phyllaries in several series; fresh plants with a strong, aromatic fragrance |
............ ............ ............ ..........24 Leaves white woolly or gray-tomentose, at least beneath (abaxially). |
............ ............ ............ ............ ..26 Plants dioecious. |
............ ............ ............ ............ ....27 Blooming Jul-Sep; leaves numerous on stem |
............ ............ ............ ............ ....27 Blooming Mar-May; leaves basally disposed |
............ ............ ............ ............ ..26 Plants not dioecious. |
............ ............ ............ ............ ......28 Bristles plumose; pappi persistent |
............ ............ ............ ............ ......28 Bristles barbellate to barbellulate; pappi falling |
............ ............ ............ ............ ........29 Pappus bristles united at their base, falling as units. |
............ ............ ............ ............ ..........30 Blooming Mar-Jul; phyllaries in 3-7 series, sometimes tinged with purple or brown but lacking a conspicuous dark brown spot |
............ ............ ............ ............ ..........30 Blooming Jul-Oct; phyllaries in 2-3 series, some or all phyllaries bearing a conspicuous (distal-middle) dark brown spot |
............ ............ ............ ............ ........29 Pappus bristles distinct, not united at the base and falling seperately. |
............ ............ ............ ............ ............ 31 Involucre < 4 mm; mature plants > 25 cm tall |
............ ............ ............ ............ ............ 31 Involucre 4-8 mm; mature plants usually > 2 dm tall |