Potentilla bruceae

Rydberg in N. L. Britton et al.

in N. L. Britton et al., N. Amer. Fl. 22: 342. 1908.

Common names: Bruce’s cinquefoil
Endemic
Synonyms: Potentilla drummondii subsp. bruceae (Rydberg) D. D. Keck P. drummondii var. bruceae (Rydberg) N. H. Holmgren
Treatment appears in FNA Volume 9. Treatment on page 159. Mentioned on page 151, 160, 170, 171.

Glands absent or inconspicuous, uncolored. Stems ascending to nearly erect, (1–) 2–5 (–6) dm. Basal leaves not in ranks, ± subpalmate to subpinnate (proximal leaflets sometimes doubled, distal leaflets confluent and/or decurrent), (2–) 5–20 (–28) cm; petiole (1–) 3–15 (–20) cm, long hairs abundant, appressed to ascending-spreading, 1–2.5 mm, weak often flattened and twisted, sometimes grading to crisped or cottony hairs, short hairs absent, glands absent or sparse; leaflets 5–7, on distal 1/10–1/4 of leaf axis, ± overlapping, largest ones usually ± obovate, (1–) 1.5–5 (–6) × 1–3.5 (–4) cm, margins flat, distal 2/3–3/4 evenly to unevenly incised ± 1/2 to midvein (often with additional incisions nearly to midvein), undivided medial blade 4–20 mm wide, teeth (2–) 3–6 (–8) per side (sometimes secondarily toothed), ± lanceolate, 4–11 mm, surfaces ± similar, abaxial ± lighter and hairier, gray-green to grayish, rarely green, not glaucous, long hairs ± abundant, short-crisped hairs absent or sparse to common, cottony hairs usually absent, glands absent or sparse. Cauline leaves 1–2. Inflorescences 5–50-flowered. Pedicels 0.5–3 (–4) cm. Flowers: epicalyx bractlets broadly lanceolate to elliptic, 3–6 (–7.5) × 1.5–2.5 (–3) mm, hairs ± common to abundant, loosely appressed to ascending, glands absent or inconspicuous; hypanthium 3.5–5.5 mm diam.; sepals 5–10 mm, apex acute to acuminate; petals 5–10 × 5–10 mm; filaments 1–2.5 mm, anthers 0.7–1.2 mm; carpels 15–30, styles filiform-tapered, papillate-swollen proximally, 2–3 mm. Achenes 1.4–1.6 mm. 2n = 63–73, 79, 87, 98, 129.


Phenology: Flowering summer.
Habitat: Dry montane meadows and adjacent slopes, in conifer woodlands
Elevation: 1200–3700 m

Discussion

As redefined by B. Ertter and D. Mansfield (2007), Potentilla bruceae is characterized by irregularly subpalmate, weakly villose leaves. Such plants form relatively consistent and extensive populations in dry meadows centered near Lake Tahoe in California and Nevada, extending to the central Sierra Nevada and to the Warner Mountains in Oregon. This interpretation differs from that previously suggested by Ertter (1992), in which P. bruceae was interpreted as the catchall category for hybrids between P. breweri (sect. Multijugae) and P. drummondii. All three taxa were accordingly treated as varieties of P. drummondii. D. D. Keck (in J. Clausen et al. 1940) treated P. bruceae as a subspecies of P. drummondii; B. C. Johnston (1980) concluded that its placement as a variety of P. breweri was more justified. The three entities unquestionably intergrade (with the type of P. anomalofolia M. Peck possibly one result), but not beyond what is the norm for facultatively apomictic species of Potentilla.

Chromosome numbers reported by J. Clausen et al. (1940) require verification as this species; the irregular behavior observed in meiotic material suggests that at least some of the individuals were hybrids.

See discussion of 29. Potentilla drummondii regarding leaflet dissection and the inclusion of P. bruceae in sect. Graciles.

Selected References

None.

Lower Taxa

None.

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

... more about "Potentilla bruceae"
129 +, 98 +, 87 +, 79 +, 63 +  and 73 +
stiff +  and weak +
green +, gray-green +  and grayish +
not glaucous +  and hairier +
1.4mm +  and 1.6mm +
blue-green +, green +  and grayish +
stiff +  and weak +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
Barbara Ertter +  and James L. Reveal +
Rydberg in N. L. Britton et al. +
less subpalmate +  and subpinnate +
20 cm200 mm <br />0.2 m <br /> (28 cm280 mm <br />0.28 m <br />) +
5 cm50 mm <br />0.05 m <br /> (20 cm200 mm <br />0.2 m <br />) +
Graciles +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
less cordate or reniform +  and narrowly elliptic +
0.5 cm5 mm <br />0.005 m <br /> (25 cm250 mm <br />0.25 m <br />) +
coriaceous +
reduced +
free +  and distinct +
hairy +  and glabrous +
Bruce’s cinquefoil +
Calif. +, Nev. +  and Oreg. +
not +  and aggregated +
1200–3700 m +
0.6 cm6 mm <br />0.006 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
broadly lanceolate +  and elliptic +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
on style scar +, hairy +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
inconspicuous +
Dry montane meadows and adjacent slopes, in conifer woodlands +
blue-green +, green +  and grayish +
straight +
loosely appressed +  and ascending +
less common +  and abundant +
short-crisped +, crisped +  and flattened +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
crassinucellate +
bipinnate +, odd-pinnate +, subpalmate +, palmate +  and ternate +
opposite +  and alternate +
stiff +  and weak +
distal +  and up-to-distal +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
5 cm50 mm <br />0.05 m <br /> (6 cm60 mm <br />0.06 m <br />) +
3.5 cm35 mm <br />0.035 m <br /> (4 cm40 mm <br />0.04 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1 cm10 mm <br />0.01 m <br /> (?) +  and 3.5 cm35 mm <br />0.035 m <br /> (?) +
linear +  and oblanceolate +
palmate +  and pinnate +
blue-green +, green +  and grayish +
stiff +  and weak +
1/2 +, 2/3 +  and 3/4 +
0.4 cm4 mm <br />0.004 m <br /> (2 cm20 mm <br />0.02 m <br />) +
blue-green +, green +  and grayish +
stiff +  and weak +
inferior +  and superior +
clustered +, biseriate +  and superposed +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
free +  and distinct +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
usually longer +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
15 cm150 mm <br />0.15 m <br /> (20 cm200 mm <br />0.2 m <br />) +
3 cm30 mm <br />0.03 m <br /> (15 cm150 mm <br />0.15 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
subpinnate +, palmate +  and subpalmate +
not flagelliform +
2 cm20 mm <br />0.02 m <br /> (40 cm400 mm <br />0.4 m <br />) +
in N. L. Britton et al., N. Amer. Fl. +
not arillate +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
stiff +  and weak +
free +  and distinct +
not rooting +
reddish +  and green +
(1.5-)2-4 times basal leaves +
ascending +  and nearly erect +
1 +  and many +
not flagelliform +
palmate +  and pinnate +
linear;ovate +
deciduous +
distinct +
subapical +
papillate-swollen +  and filiform-tapered +
rough-thickened +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
blue-green +, green +  and grayish +
stiff +  and weak +
incised +, flat +  and more or less revolute +
Potentilla drummondii subsp. bruceae +  and P. drummondii var. bruceae +
not fleshy-thickened +
Potentilla bruceae +
Potentilla sect. Graciles +
species +
blue-green +, green +  and grayish +
stiff +  and weak +
3 +  and 6 +
lanceolate +
0.4 cm4 mm <br />0.004 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
inconspicuous +
enlarged +
biennial +, annual +  and perennial +
herb +  and matted +