| |
| L. occidentalis |
| | 2' Ligules purple, pink, or white |
| L. filaginifolia |
| | 3. Heads 1–5 per stem; involucres ± as long as wide; disk corollas 6–8 mm |
| var. californica |
| | 3' Heads 3–20+ per stem; involucres ± 2 × as long as wide; disk corollas 4–6 mm |
| var. filaginifolia |
| |
| | 4. Corollas yellow (except sometime pink marginal flowers of L. tenuis) |
| |
| | 5. Plants without glands, or only the phyllaries with sparse, nail-shaped glands |
| L. germanorum |
| | 5' Plants with nail- and or tack-shaped glands |
| |
| | 6. Margins of cauline leaves without glands; tips of inner phyllaries generally purple or purple-tinged |
| L. tenuis |
| | 6' Margins of cauline leaves glandular; tips of inner phyllaries generally green |
| |
| | 7. Phyllaries with glands on margins and back of tips; plants generally rigidly much-branched; cauline leaves much reduced upward |
| L. glandulifera |
| | 8. Stems prostrate, herbage densely tomentose |
| var. tomentosa |
| | 8' Stems erect, herbage glabrous or thinly tomentose |
| |
| var. glandulifera |
| var. pectinata |
| | 7' Phyllaries with glands on margins only; plants generally flexible, few-branched; cauline leaves only slightly reduced upwards |
| L. lemmonii |
| var. peirsonii |
| | 10' Phyllaries puberulent |
| |
| | 11. Cauline leaves not clasping base of involucre |
| var. lemmonii |
| | 11' Cauline leaves clasping base of involucre |
| var. ramulosissima |
| | 4' Corollas white, purple, or pink |
| |
| | 12. Phyllaries glabrous or puberulent |
| |
| | 13. Involucres widely obconic to bell-shaped; basal leaves many, present at flowering |
| L. ramulosa |
| | 13' Involucres narrowly obconic; basal leaves few, generally withering before flowering |
| |
| | 14. Corollas funnel-shaped; style-branch appendages 0.5–0.9 mm, without abrupt point |
| L. nemaclada |
| | 14' Corollas tubular; style-branch appendages < 0.3 mm, with evident abrupt point |
| L. micradenia |
| | 15. Margins of cauline leaves without glands |
| var. glabrata |
| | 15' Margins of cauline leaves with glands |
| var. micradenia |
| | 12' Phyllaries woolly or tomentose |
| |
| | 16. Tips of inner phyllaries white |
| L. nana |
| | 16' Tips of inner phyllaries green, scarious, or purplish |
| |
| | 17. Herbage without glands |
| |
| | 18. Pappus < fruit; style appendages short-triangular, 0.2–0.4 mm; basal leaves generally fallen before flowering, glabrous if present |
| L. arachnoidea |
| | 18' Pappus = or > than fruit; style appendages tapered, 0.6–0.8 mm; basal leaves present at flowering, tomentose |
| L. hololeuca |
| |
| | 19. Flowers 6–25 per head; leaves and stems glabrous or hairy; cauline leaves with glandular dots only; branches slender, flexible, spreading |
| L. leptoclada |
| | 19' Flowers 3–6 per head; leaves and stems persistently tomentose, at least in part; cauline leaves with sessile and stalked glands; branches stout, wand-like, ascending |
| L. virgata
|