Orobanche vallicola
Madroño 22: 64. 1973.
Plants simple or few-branched, 7–40 cm, stout, base usually enlarged. Roots usually inconspicuous, slender, branched or unbranched. Leaves numerous, erect; blade broadly triangular proximally, grading to lanceolate distally, 7–10 mm, margins entire, apex obtuse, acute on distal leaves, surfaces glabrous. Inflorescences racemes, sometimes spikelike, pink, lavender, or yellow, sometimes branched, glandular-puberulent; flowers numerous; bracts usually reflexed toward tips, narrowly triangular to lanceolate-linear or subulate, 5–10 mm, apex attenuate, glandular-puberulent. Pedicels 5–25 mm, much shorter than plant axis; bracteoles 2. Flowers: calyx pale or pinkish tinged, ± radially symmetric, (6–)9–15(–20) mm, deeply divided into 5 lobes, lobes narrowly subulate, glandular-puberulent; corolla 17–28(–33) mm, tube white to pale yellow or pale pink, slightly constricted above ovary, straight or slightly bent forward, sparsely glandular-pubescent or glabrate; palatal folds prominent, yellow, glabrous; lips white to pale pink, often with darker pink veins, abaxial lip usually widely spreading, 5–9(–10) mm, lobes narrowly oblong-triangular to lanceolate, apex acute, adaxial lip usually widely spreading, 5–9(–10) mm, lobes triangular or triangular-ovate, apex acute; filaments glabrous, anthers included, glabrous or ± villous along sutures. Capsules ovoid to cylindric-ovoid, 10–13 mm. Seeds 0.4–0.5 mm.
Phenology: Flowering (Mar–)May–Nov.
Habitat: Woodlands, thickets, openings, lowland valleys and foothills.
Elevation: 0–400 m.
Discussion
Orobanche vallicola is rare but occurs occasionally in widely scattered localities in cismontane California from Trinity County south to Los Angeles County.
The most frequently reported host for Orobanche vallicola is Sambucus (Adoxaceae), but O. vallicola has also been reported on Baccharis douglasii and Ericameria nauseosa (Asteraceae), Pyrus (Rosaceae), Quercus agrifolia (Fagaceae), and Symphoricarpos albus (Caprifoliaceae) (L. R. Heckard 1973).
Selected References
None.