Eriogonum umbellatum var. nelsoniorum

Reveal

Phytologia 86: 151. 2004.

Common names: Nelson’s sulphur flower
Treatment appears in FNA Volume 5. Treatment on page 348. Mentioned on page 339.

Subshrubs or herbs, spreading, 1–2.5 × 2–7 dm. Aerial flowering-stems erect, 1–2 dm, thinly floccose, without one or more leaflike bracts ca. midlength. Leaves in rather loose rosettes; blade elliptic to oblong, (0.5–) 1–1.5 (–2) × 0.4–0.8 cm, densely white-tomentose to lanate abaxially, white-tomentose to floccose or rarely glabrate and greenish adaxially, margins plane. Inflorescences umbellate, 1–3 cm; branches 1–2 cm, thinly floccose, without a whorl of bracts ca. midlength; involucral tubes 3–4 mm, lobes 2–4 mm. Flowers (5–) 6–7 mm; perianth bright-yellow.


Phenology: Flowering Jul–Sep.
Habitat: Sandy to gravelly serpentine slopes, oak and montane conifer woodlands
Elevation: 1500-2300 m

Discussion

Variety nelsoniorum is somewhat similar morphologically to var. argus but probably more closely related to var. bahiiforme. It differs from both in consistently having a simple, rather than compound-umbellate, inflorescence. The large bracts that subtend the umbel are long (1–1.5 cm) and leaflike, like those of var. bahiiforme, but the distribution of tomentum of the leaf blades is like that of var. argus. All three occur on serpentine soils. However, var. nelsoniorum is found only in Humboldt and Trinity counties, or basically north of var. bahiiforme and southwest of var. argus. A series of small populations in the Scott Bar Mountains of Siskiyou County may prove to be var. nelsoniorum.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property.

light-brown;brown +
included +  and exserted +
3-gonous +
usually red +  and cream or yellow +
oblong +  and ellipsoid or oval +
James L. Reveal +
Reveal +
deciduous +  and persistent +
stipelike +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
awn-tipped +  and simple +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
densely white-tomentose +  and lanate abaxially +
elliptic;oblong +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
not awn-tipped +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
midlength +
glandular +, pubescent +  and glabrous +
3;several +
scale-like +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
grooved +, disarticulating +  and dichotomous +
not brittle +
scabrellous +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
spreading +  and erect +
whorled +, opposite +  and alternate +
Nelson’s sulphur flower +
1500-2300 m +
curved +  and straight +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
unisexual +  and bisexual +
attenuate +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
decumbent to erect +  and prostrate +
not fistulose +
unwinged +  and winged +
black +, red +, brown +  and yellowish +
exserted +  and included +
pubescent +  and glabrous +
spheroidal +, 4-gonous +, lenticular +, biconvex +, discoid +, 3-gonous +  and 2-gonous +
Sandy to gravelly serpentine slopes, oak and montane conifer woodlands +
capitate +  and subcapitate +
3 cm30 mm <br />0.03 m <br /> (25 cm250 mm <br />0.25 m <br />) +
cymelike +, paniclelike +, racemelike +  and spikelike +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
2 cm20 mm <br />0.02 m <br /> (18 cm180 mm <br />0.18 m <br />) +
connate +  and free +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
tomentose +  and thinly floccose or glabrous +
turbinate +  and campanulate +
nonmembranous +
0.15 cm1.5 mm <br />0.0015 m <br /> (1 cm10 mm <br />0.01 m <br />) +
in whorls +, opposite +, alternate +  and rosulate +
persistent +
cauline +  and basal +
bractlike +
pubescent +  and glabrous +
not swollen +
orthotropous +
accrescent +
curved +  and straight +
erect to deflexed +
bright-yellow +
cylindric +  and urceolate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
mostly tomentose +  and floccose or glabrous +
0.1 cm1 mm <br />0.001 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Flowering Jul–Sep. +
homostylous +  and 3-carpellate +
0.3 cm3 mm <br />0.003 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
, +  and solid +
slender;stout +
persistent +
Illustrated +  and Endemic +
0.2 cm2 mm <br />0.002 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
decumbent to erect +  and prostrate +
prostrate +  and erect +
glandular +, pubescent +  and glabrous +
penicillate +, fimbriate +  and capitate +
deciduous +  and persistent +
2-lobed +  and cylindric +
coriaceous +  and membranous +
consisting of a series +  and tubular +
distinct +
erect;spreading or recurved +
spreading;erect +
chambered +  and solid +
slender +  and stout +
Eriogonum umbellatum var. nelsoniorum +
Eriogonum umbellatum +
variety +
emarginate +  and entire +
1/4 +  and 1/3 +
usually spatulate +  and obovate +
coriaceous +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
involucral +
persistent +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
membranous +
pubescent +  and glabrous +
sericeous +, lanate +  and tomentose floccose or glabrous +
dioecious +, polygamodioecious +, synoecious +  and polycarpic +
annual +, biennial +  and perennial +
herb +  and subshrub +
spreading;spreading +
tomentose +  and glabrous +
midlength +
3 +, 2 +  and 1 +