Jepson eFlora
Key to families | Table of families and genera

Key to Orobanche

View taxon page for Orobanche

1. Calyx 4-lobed, cut deeper on upper side; inflorescence open, flowers sessile, becoming well separated — pest on vegetable crops ..... O. ramosa

1' Calyx 5-lobed, cut equally or deeper on lower side; inflorescence dense, generally remaining so; at least proximal flowers ± pedicelled

2. Pedicels 3–15 cm, bractlets on pedicel 0; flowers 1–20; nectary gland at base of ovary evident

3. Flowers generally 5–20; bracts > 6; distal pedicels < stem; corolla generally ± pink or yellow, lobes glabrous to soft-hairy; generally on Artemisia, Eriodictyon, Eriogonum, Galium ..... O. fasciculata

3' Flowers generally 1–3; bracts generally < 6; distal pedicels > stem; corolla generally pale ± purple to ± yellow, lobes minutely ciliate; generally on Sedum, Saxifragaceae, Asteraceae ..... O. uniflora

2' Pedicels < 2(5) cm, bractlets on pedicel 2; flowers generally > 20; nectary gland at base of ovary obscure

4. Inflorescence and flowers ± yellow to dark purple (may be ± red in Orobanche pinorum); calyx generally 5–12 mm

5. Calyx divided nearly to base on lower side; hairs of inflorescence and corolla papillate, not glandular; on Adenostoma ..... O. bulbosa

5' Calyx divided ± equally; most hairs of inflorescence and corolla glandular, not papillate; on various genera

6. Corolla with ring of hairs at base of filaments; root attachment rounded, coral-like; on Holodiscus ..... O. pinorum

6' Corolla lacking ring of hairs; root attachment branched (rarely rounded, coral-like in Orobanche cooperi)

7. Inflorescence 4–5 cm wide; corolla 18–32 mm, lips 5–10 mm; on Asteraceae ..... O. cooperi

7' Inflorescence 2–3 cm wide; corolla 12–18 mm, lips 3–5 mm; on Garrya ..... O. valida

8. Corolla 14–18 mm, hairy outside, densely so at sinuses, hairs 0.4–0.7 mm; filament base and anther hairy ..... subsp. howellii

8' Corolla 12–14 mm, puberulent outside, sparsely so to glabrous at sinuses, hairs ± 0.1 mm; filament base and anther glabrous ..... subsp. valida

4' Inflorescence and flowers generally buff to ± pink, corolla lips white to pink or lavender, occasionally with darker veins (some populations of Orobanche californica, Orobanche parishii subsp. parishii darker-flowered); calyx generally 10–20 mm

9. Corolla 13–30 mm, lips 4–10 mm

10. Inflorescence branched, forming convex or ± flat-topped cluster; flowers crowded; corolla tube with prominent hump on upper side, lobes erect; anthers densely hairy throughout; generally on Artemisia tridentata; n Cascade Range, High Sierra Nevada, Great Basin Floristic Province, n Desert Mountains ..... O. corymbosa

10' Inflorescence of elongate, generally unbranched, ± raceme-like units; flowers less crowded and more regularly-spaced; corolla tube without prominent hump on upper side, lobes various; anthers glabrous or hairy along dehisced margin; on Artemisia, other Asteraceae

11. Flowers pedicelled throughout; bracts lanceolate; mature flower corolla lobes strongly recurved, narrowly acute ..... O. vallicola

11' Only proximal flowers pedicelled; bracts ± ovate; mature flower upper corolla lobes slightly recurved at tip, rounded or obtuse ..... O. parishii

12. Corolla 15–24 mm, lips 4–6 mm; calyx lobes generally 7–10 mm; sandy soil near ocean ..... subsp. brachyloba

12' Corolla 20–25 mm, lips 6–8 mm; calyx lobes 10–16 mm; dry openings in forest, chaparral, scrub ..... subsp. parishii

9' Corolla 20–50 mm, lips 10–14 mm, (see also Orobanche corymbosa for plants of High Sierra Nevada, Great Basin Floristic Province) ..... O. californica

13. Corolla lavender to purple; calyx lobes, pedicels, and bracts similarly colored, drying dark purple; North Coast, n&c Central Coast ..... subsp. californica

13' Corolla white to ± yellow to ± pink or ± red-tinged; calyx lobes, pedicels, and bracts pale to pink-tinged, drying brown; generally California Floristic Province (inland except Orobanche californica subsp. grandis), Modoc Plateau, s East of Sierra Nevada

14. Corolla tube ± stout, > 4 mm wide at constriction, abruptly expanded to form hump-back throat

15. Stem delicate; ± 500 m; s Central Coast, Inner South Coast Ranges, Outer South Coast Ranges, w Western Transverse Ranges ..... subsp. condensa

15' Stem stout; 700–2500 m; s High Sierra Nevada, Tehachapi Mountain Area, Transverse Ranges, Peninsular Ranges, s East of Sierra Nevada, Mojave Desert ..... subsp. feudgei

14' Corolla tube slender below, < 4 mm wide at constriction, gradually expanded

16. Corolla 35–50 mm, lower lobes narrowly ovate, > 5 mm wide; generally on Corethrogyne filaginifolia; coastal dunes, marine terraces; s Central Coast, s Outer South Coast Ranges (Santa Barbara Co.), c South Coast (Los Angeles Co.), n Channel Islands (Santa Rosa Island) ..... subsp. grandis

16' Corolla 20–40 mm, lower lobes narrowly triangular to oblong, < 5 mm wide

17. Plant 4–10 cm; stem proximal to inflorescence 1–5 cm; inflorescence a convex to ± flat-topped cluster < 5 cm; on Asteraceae; moist or vernally wet meadows, stream margins ..... subsp. grayana

17' Plant 10–35 cm; stem proximal to inflorescence generally > 6 cm; inflorescence elongate, 5–20 cm; generally dry places; on various perennial herb and shrub Asteraceae ..... subsp. jepsonii


Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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