Orobanche valida subsp. howellii

Heckard & L. T. Collins

Madroño 29: 98, fig. 1A–E. 1982.

Common names: Howell’s broomrape
Endemic
Synonyms: Aphyllon validum subsp. howellii (Heckard & L. T. Collins) A. C. Schneider
Treatment appears in FNA Volume 17. Treatment on page 486. Mentioned on page 485.

Plants (6–) 10–20 cm, base often slightly enlarged. Bracts, bracteoles, and calyces densely glandular-pilose, hairs 0.2–0.4 mm. Corollas 14–16 (–18) mm; palatal folds puberulent; lips and tube densely glandular-pilose throughout, hairs 0.4–0.7 mm; filaments sparsely pilose at base, anthers pilose. 2n = 48.


Phenology: Flowering Jun–Sep.
Habitat: Rocky volcanic, serpentine slopes, open chaparral.
Elevation: 1200–1700 m.

Discussion

Subspecies howellii is restricted to Glenn, Lake, Mendocino, Napa, and Tehama counties in the northern and central Coast Ranges, geographically disjunct from subsp. valida. The confirmed hosts are species of Garrya. Reports of Eriodictyon and Quercus as hosts need confirmation. Further research on this rare subspecies is warranted to establish its range and conservation status.

Selected References

None.

Lower Taxa

None.

usually white +  and pale lavender +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
reflexed +  and erect +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
glandular-pubescent +
Acute (?) +, Pointed (?) +, Acuminate (?) +  and Obtuse (?) +
L. Turner Collins +, Alison E. L. Colwell +  and George Yatskievych +
Heckard & L. T. Collins +
enlarged +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
not leathery +, not +  and fleshy +
ascending +  and recurved +
narrowly lanceolate-acuminate +  and lanceolate-subulate +
1 cm10 mm <br />0.01 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
dark purple +
glandular-pilose +
divided +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
narrowly ovoid;oblong-ovoid +
0.6 cm6 mm <br />0.006 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
Howell’s broomrape +
1.6 cm16 mm <br />0.016 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
pallid +, tinged pink +  and purple yellow or blue +
Bent (?) +  and Tubular (?) +
constricted +
1.4 cm14 mm <br />0.014 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
spikelike +
1200–1700 m. +
pale-yellow;white +
puberulent +
indehiscent +, septicidal +, loculicidal +  and dehiscence +
Rocky volcanic, serpentine slopes, open chaparral. +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
dark purple;creamy white +
axillary +  and terminal +
pilose +  and glandular-pubescent +
deciduous +
dark purple +
glandular-pilose +
loosely ascending +  and recurved +
glandular-pubescent +
triangular +, narrowly oblong +  and oblong-triangular +
erosulate +, erose +  and entire +
lobed +, toothed +  and entire +
tenuinucellate +  and unitegmic +
campylotropous-like +
spikelike +
0 cm0 mm <br />0 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Flowering Jun–Sep. +
spikelike +
branched +  and unbranched +
inconspicuous +
coralloid +
slender +
500 +  and 2000 +
prismatic +, ovoid +  and oblong-ellipsoid +
5 +  and 4 +
subequal +
yellow +  and white +
aerial +  and subterranean +
capitate +  and crateriform-peltate +
clavate +  and 2-4-lobed +
Aphyllon validum subsp. howellii +
Orobanche valida subsp. howellii +
Orobanche valida +
subspecies +
yellow;white +
glandular-pilose +
constricted +
with a few short branches +  and simple +
perennial +  and annual +
holoparasitic +  and hemiparasitic +