Eriogonum twisselmannii

(J. T. Howell) Reveal in P. A. Munz

in P. A. Munz, Suppl. Calif. Fl. 40. 1968.

Common names: Twisselmann’s wild buckwheat
EndemicConservation concern
Basionym: Eriogonum douglasii var. twisselmannii J. T. Howell Leafl. W. Bot. 10: 13. 1963
Treatment appears in FNA Volume 5. Treatment on page 364. Mentioned on page 332.

Herbs, matted, occasionally polygamodioecious, (0.2–) 0.5–1.5 × 3–4 dm, tomentose. Stems: caudex spreading; aerial flowering-stems erect or nearly so, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, nonflowering aerial branches, (0.2–) 0.5–1.2 dm, tomentose, with a whorl of 4–8 leaflike bracts ca. midlength, similar to leaf-blades, 0.4–0.8 × 0.1–0.3 cm. Leaves in loose to congested basal rosettes; petiole 0.2–0.4 cm, thinly tomentose; blade oblanceolate to elliptic, 0.5–1 × (0.2–) 0.4–0.6 cm, white or grayish-tomentose abaxially, thinly tomentose to nearly glabrous and dull green adaxially. Inflorescences capitate, 0.7–1.5 cm wide; branches absent; bracts absent immediately below involucre. Involucres 1 per node, campanulate, (2.5–) 4–5 × 4–6 mm; teeth 6–9, lobelike, strongly reflexed, (2–) 3–5 mm. Flowers (4–) 5–6 mm, including 1–1.3 mm stipelike base; perianth pale-yellow, villous abaxially; tepals slightly dimorphic, those of outer whorl obtuse, 3–5 × 3–3.5 mm, those of inner whorl broadly oblanceolate, 5–6 × 2.5–3 mm; stamens exserted, 4–5 mm; filaments pilose proximally. Achenes light-brown, 5–5.5 mm, glabrous except for sparsely pubescent beak.


Phenology: Flowering Jun–Sep.
Habitat: Rocky outcrops, montane conifer woodlands
Elevation: 2300-2600 m

Discussion

Of conservation concern.

Eriogonum twisselmannii is a rare species of the southern Sierra Nevada and is known only from Slate Mountain and The Needles in Tulare County. It is worthy of being on a “watch” list of rare plants in California, but because of its remote location, it is not threatened.

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

... more about "Eriogonum twisselmannii"
light-brown +
included +  and exserted +
3-gonous +
usually red +  and cream or yellow +
oblong +  and ellipsoid or oval +
James L. Reveal +
(J. T. Howell) Reveal in P. A. Munz +
deciduous +  and persistent +
loose to congested +
stipelike +
0.1 cm1 mm <br />0.001 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
Eriogonum douglasii var. twisselmannii +
awn-tipped +  and simple +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
green +  and white +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
thinly tomentose +  and nearly glabrous +
oblanceolate;elliptic +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
not awn-tipped +
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 +
Twisselmann’s wild buckwheat +
2300-2600 m +
curved +  and straight +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
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 +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
not fistulose +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
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 +
Rocky outcrops, montane conifer woodlands +
open +, simple +  and compound-umbellate +
cymelike +, paniclelike +, racemelike +  and spikelike +
0.7 cm7 mm <br />0.007 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
connate +  and free +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
campanulate +
nonmembranous +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
in whorls +, opposite +, alternate +  and rosulate +
persistent +
cauline +  and basal +
bractlike +
pubescent +  and glabrous +
lobed +, undulate +, crisped +, crenulate +  and entire +
not swollen +
orthotropous +
accrescent +
curved +  and straight +
erect to deflexed +
cylindric +  and urceolate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Flowering Jun–Sep. +
homostylous +  and 3-carpellate +
in P. A. Munz, Suppl. Calif. Fl. +
, +  and solid +
slender;stout +
persistent +
Endemic +  and Conservation concern +
0.4 cm4 mm <br />0.004 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 +
chambered +  and solid +
slender +  and stout +
Eriogonum twisselmannii +
Eriogonum subg. Oligogonum +
species +
emarginate +  and entire +
1/4 +  and 1/3 +
lobed +  and laciniate +
coriaceous +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
persistent +
membranous +
pubescent +  and glabrous +
sericeous +, lanate +  and tomentose floccose or glabrous +
dioecious +, polygamodioecious +, synoecious +  and polycarpic +
annual +, biennial +  and perennial +
herb +  and matted +
midlength +
3 +, 2 +  and 1 +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +