Ivesia webberi

A. Gray

Proc. Amer. Acad. Arts 10: 71. 1874.

Common names: Webber’s or wire ivesia
Conservation concernEndemic
Synonyms: Potentilla webberi (A. Gray) Greene
Treatment appears in FNA Volume 9. Treatment on page 236. Mentioned on page 219, 230, 231, 237.

Plants ± green, ± rosetted; taproot slender to ± stout, not fleshy. Stems decumbent to ascending, 0.5–1.5 (–1.8) dm. Basal leaves loosely ± cylindric, 3–7 (–10) cm; sheathing base ± strigose abaxially; petiole 0.5–5 (–6) cm, hairs 2–4 mm; leaflets 4–8 (–10) per side, (0.5–) 3–8 (–10) mm, loosely long-strigose or villous and short-hirsute, ± glandular, lobes 2–5 (–12), linear to lanceolate, apex not setose. Cauline leaves 2, paired. Inflorescences 5–15 (–25) -flowered, 1.5–3 (–6) cm diam.; glomerules 1. Pedicels (0.5–) 1–8 (–13) mm. Flowers 9–12 mm diam.; epicalyx bractlets linear, 1.2–3 mm; hypanthium cupulate, 1–2 (–2.5) × 2.5–5 mm; sepals 2.5–4.5 (–5.5) mm, acute; petals yellow, narrowly oblanceolate, 2–3 (–4) mm; stamens 5, filaments 1.8–2.5 (–3) mm, anthers yellow, (0.8–) 1–1.6 mm; carpels 3–8, styles 1.8–2.2 mm. Achenes light-brown, often mottled darker brown, 1.9–2.5 mm.


Phenology: Flowering late spring–early summer.
Habitat: Dry flats and slopes, in sagebrush communities, conifer woodlands
Elevation: (1300–)1500–1900 m

Discussion

Of conservation concern.

Ivesia webberi is known only from the eastern foothills of the northern Sierra Nevada and scattered ranges to the east in California and adjacent Nevada. It is among the more distinctive species in the genus and is only tentatively placed in sect. Ivesia. The leaflets are loosely incised into slender, sparsely villous segments, and the two cauline leaves are paired with dissected stipules. Previous reports of the stems and inflorescence branches being glandular-puberulent are due to a misinterpretation of the minute pustulose bases associated with the villous indumentum as being enlarged glands.

Selected References

None.

Lower Taxa

None.

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

... more about "Ivesia webberi"
not carunculate +
brown +, mottled darker +  and light-brown +
1.9mm +  and 2.5mm +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
longer than wide +
0.1 cm1 mm <br />0.001 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
not setose +
Barbara Ertter +  and James L. Reveal +
A. Gray +
compound +  and simple +
opposite +  and alternate +
7 cm70 mm <br />0.07 m <br /> (10 cm100 mm <br />0.1 m <br />) +
3 cm30 mm <br />0.03 m <br /> (7 cm70 mm <br />0.07 m <br />) +
20 cm200 mm <br />0.2 m <br /> (25 cm250 mm <br />0.25 m <br />) +
narrowly oblong +  and filiform planar +
reduced +
0.5 cm5 mm <br />0.005 m <br /> (20 cm200 mm <br />0.2 m <br />) +
reduced +
elongate +
free +  and distinct +
branched +  and simple +
Webber’s or wire ivesia +
Calif. +  and Nev. +
not +  and aggregated +
(1300–)1500–1900 m +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.9 cm9 mm <br />0.009 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
obliquely ovoid +  and reniform +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
loose +  and capitate +
Dry flats and slopes, in sagebrush communities, conifer woodlands +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
5-15(-25)-flowered +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
crassinucellate +
opposite +  and alternate +
winter-marcescent +
deciduous +  and persistent +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
, +  and distinct +
not +  and distinguishable +
short-hirsute +, villous +  and long-strigose +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
linear +  and lanceolate +
verticillate +
toothed +, unlobed +  and lobed +
inferior +  and superior +
clustered +, biseriate +  and superposed +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0 (?) +  and 4 (?) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
free +  and distinct +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
5 cm50 mm <br />0.05 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Flowering late spring–early summer. +
adnate +, free +, connate +  and distinct +
Proc. Amer. Acad. Arts +
not arillate +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
persistent +
free +  and distinct +
erect +  and spreading +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Conservation concern +  and Endemic +
free +  and distinct +
branched +  and simple +
reddish +, grayish +  and green +
decumbent +  and ascending +
2 +  and 20 +
palmate +  and pinnate +
deciduous +
distinct +
subterminal +
filiform +
rough-thickened +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
Potentilla webberi +
not fleshy +
Ivesia webberi +
Ivesia sect. Ivesia +
species +
inconspicuous +
stipelike +, elongate +, less flat +  and conic or turbinate +
enlarged +
glabrate +  and sparsely densely glandular-puberulent +