Eriogonum ursinum var. ursinum

Common names: Bear Valley wild buckwheat
Endemic
Synonyms: Eriogonum ovatum Greene
Treatment appears in FNA Volume 5. Treatment on page 358.

Plants 0.5–4 × 3–6 dm. Aerial flowering-stems 0.4–4 dm, thinly tomentose to glabrate. Leaves: petiole 0.1–0.5 (–0.8) cm; blade ovate, 0.8–1.4 (–2.5) × 0.5–1.2 (–2) cm, densely white or rufous-tomentose abaxially, thinly tomentose or glabrous and greenish adaxially. Inflorescences thinly tomentose to glabrate; proximal bracts 3–8, lanceolate, 0.5–1.5 (–2) × 0.3–1 cm, distal bracts scalelike, not midway along branch, 1–5 mm. Involucres turbinate, 3.5–4.5 (–5) × 2.5–4 mm. Flowers 4–6 mm at anthesis, 5–6 mm in fruit; perianth pale-yellow, rarely yellow, not suffused with blush of color. Achenes 3–3.5 mm.


Phenology: Flowering May–Sep.
Habitat: Sandy to gravelly, mostly volcanic flats and slopes, oak and montane conifer woodlands
Elevation: (500-)900-2500(-2800) m

Discussion

Variety ursinum is rather common in the northern Sierra Nevada (Lassen, Nevada, Placer, Plumas, Shasta, and Sierra counties), with a series of disjunct populations on the Trinity-Tehama-Shasta county lines. A low-elevation population (Hutchinson et al. 2693, JEPS) is known from near Pulga along the Feather River in Butte County.

Bear Valley wild buckwheat forms large, colorful mats on the forest floor, with rather compact but compound umbels of pale yellow flowers. The plants do well in the garden. A specimen (T. J. Howell s.n., NY) supposedly gathered somewhere in Oregon is discounted as to location.

Selected References

None.

Lower Taxa

None.

"/2" 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.

0.5 cm5 mm <br />0.005 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
light-brown +
included +  and exserted +
3-gonous +
usually red +  and cream or yellow +
oblong +  and ellipsoid or oval +
James L. Reveal +
S. Watson +
deciduous +  and persistent +
stipelike +
0.1 cm1 mm <br />0.001 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
awn-tipped +  and simple +
1.4 cm14 mm <br />0.014 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (2 cm20 mm <br />0.02 m <br />) +
greenish +  and white +
0.8 cm8 mm <br />0.008 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
glabrous +, tomentose +  and rufous-tomentose +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
not awn-tipped +
leaflike +  and semileaflike +
glandular +, pubescent +  and glabrous +
scale-like +
grooved +, disarticulating +  and dichotomous +
not brittle +
tomentose +  and floccose or glabrous +
scabrellous +
spreading +  and erect +
whorled +, opposite +  and alternate +
Bear Valley wild buckwheat +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
(500-)900-2500(-2800) m +
curved +  and straight +
not suffused with blush +
unisexual +  and bisexual +
attenuate +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 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, mostly volcanic flats and slopes, oak and montane conifer woodlands +
compound-umbellate +
subcapitate +  and capitate +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
thinly tomentose +  and glabrate +
cymelike +, paniclelike +, racemelike +  and spikelike +
1 cm10 mm <br />0.01 m <br /> (5 cm50 mm <br />0.05 m <br />) +
connate +  and free +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
nonmembranous +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 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 +
not suffused with blush;yellow;pale-yellow +
glabrous +  and pubescent +
cylindric +  and urceolate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Flowering May–Sep. +
homostylous +  and 3-carpellate +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Proc. Amer. Acad. Arts +
, +  and solid +
slender;stout +
persistent +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 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 +
Eriogonum ovatum +
chambered +  and solid +
slender +  and stout +
Eriogonum ursinum var. ursinum +
Eriogonum ursinum +
variety +
emarginate +  and entire +
1/4 +  and 1/3 +
obovate +  and ovate +
coriaceous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
persistent +
membranous +
pubescent +  and glabrous +
sericeous +, lanate +  and tomentose floccose or glabrous +
dioecious +, polygamodioecious +, synoecious +  and polycarpic +
annual +, biennial +  and perennial +
thinly tomentose +  and floccose or glabrate +
2 (?) +  and 8 (?) +
3 +, 2 +  and 1 +