Potentilla biennis

Greene

Fl. Francisc., 65. 1891.

Common names: Biennial or Greene’s cinquefoil
Endemic
Treatment appears in FNA Volume 9. Treatment on page 140. Mentioned on page 137, 138, 139.

Stems ascending to erect, (1–) 2–6 (–8.5) dm, hairs at base not stiff, not tubercle-based, glands sparse to abundant, conspicuous (to 1 mm, septate). Leaves ternate, (2–) 4–12 (–25) cm; petiole (1–) 2–8 (–20) cm, long hairs sparse to common, spreading to ascending, 0.5–1.5 (–3) mm, weak, crisped hairs usually absent, glands sparse to abundant, conspicuous (to 1 mm, septate); leaflets 3, at tip of leaf axis, usually overlapping, largest ones mostly obovate or oval to nearly round, (0.5–) 1–3 (–4) × 0.3–3 (–3.5) cm, distal 3/4 to ± whole margin evenly to unevenly incised 1/4–1/3 (–1/2) to midvein, teeth 3–8 (–13) per side, surfaces sparsely to moderately hairy, rarely glabrate, glands sparse to abundant at least abaxially. Inflorescences (10–) 20–70+-flowered. Pedicels 0.2–1 (–2) cm. Flowers: epicalyx bractlets narrowly oblanceolate to narrowly obovate or elliptic, (1.5–) 2–3.5 (–4.5) × 0.5–1.5 (–2) mm; hypanthium (2–) 3–4 (–5.5) mm diam.; sepals (2–) 3–5 mm, apex broadly acute to obtuse; petals pale-yellow to yellow, broadly oblanceolate to obovate, (1–) 2–2.7 × 1.5 mm; stamens 10 or 15, filaments 0.5–1.2 mm, anthers 0.2–0.3 mm; carpels 40–100, styles 0.5–0.7 mm. Achenes whitish or pale yellowish, 0.5–0.9 mm, smooth, without a corky protuberance.


Phenology: Flowering summer.
Habitat: Moist meadows, stream banks, ditches, seepages
Elevation: 400–3100 m

Distribution

V9 202-distribution-map.jpg

Alta., B.C., Sask., Yukon, Alaska, Ariz., Calif., Colo., Idaho, Mont., Nev., N.Mex., N.Dak., Oreg., Utah, Wash., Wyo.

Discussion

Potentilla biennis may be recognized by its septate hairs with a round, terminal gland, which dominate the vestiture especially at the base of the plant. Stems are more commonly erect and leaflets rounder than those of P. rivalis. The species is most common along the eastern side of the Sierra Nevada of California, across the Intermountain Region to the Rocky Mountains. All specimens seen by the authors from Baja California, Mexico, which were previously referred to P. biennis are now assigned to P. rivalis.

J. Soják (1996) lectotypified Potentilla millegrana Engelmann ex Lehmann upon a collection of P. rivalis, thus preventing P. biennis from being a later taxonomic synonym.

Selected References

None.

Lower Taxa

None.

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

... more about "Potentilla biennis"
pale yellowish +  and whitish +
smooth +  and strongly rugose +
0.5mm +  and 0.9mm +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
Barbara Ertter +  and James L. Reveal +
Greene +
15 cm150 mm <br />0.15 m <br /> (25 cm250 mm <br />0.25 m <br />) +
3 cm30 mm <br />0.03 m <br /> (15 cm150 mm <br />0.15 m <br />) +
compound +  and simple +
opposite +  and alternate +
not stiff +
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 />) +
reduced +
free +  and distinct +
hairy +  and glabrous +
Biennial or Greene’s cinquefoil +
Alta. +, B.C. +, Sask. +, Yukon +, Alaska +, Ariz. +, Calif. +, Colo. +, Idaho +, Mont. +, Nev. +, N.Mex. +, N.Dak. +, Oreg. +, Utah +, Wash. +  and Wyo. +
not +  and aggregated +
400–3100 m +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
narrowly oblanceolate +  and narrowly obovate or elliptic +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 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 />) +
conspicuous +
Moist meadows, stream banks, ditches, seepages +
not tubercle-based +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
straight +
spreading +  and ascending +
sparse +  and common +
crisped +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 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 />) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 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 />) +
(10-)20-70+-flowered +
crassinucellate +
opposite +  and alternate +
12 cm120 mm <br />0.12 m <br /> (25 cm250 mm <br />0.25 m <br />) +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
4 cm40 mm <br />0.04 m <br /> (12 cm120 mm <br />0.12 m <br />) +
separate +  and overlapping +
linear +  and oblanceolate +
palmate +  and pinnate +
1/4 +  and 1/3-1/2 +
inferior +  and superior +
clustered +, biseriate +  and superposed +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
free +  and distinct +
0.2 cm2 mm <br />0.002 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (?) +
8 cm80 mm <br />0.08 m <br /> (20 cm200 mm <br />0.2 m <br />) +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
often more or less longer +
Fl. Francisc., +
not arillate +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
free +  and distinct +
not rooting +
reddish +  and green +
(1-)2-5(-12) times basal leaves +
ascending +  and erect +
1 +  and many +
not flagelliform +
palmate +  and pinnate +
deciduous +
distinct +
papillate-swollen +
subapical +
conic-tapered +
rough-thickened +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
glabrate +  and hairy +
Potentilla sect. Supinae +, Potentilla ser. +  and Undefined sect. Tridophyllum +
not fleshy-thickened +
Potentilla biennis +
Potentilla sect. Rivales +
species +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
3 cm30 mm <br />0.03 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
1cm +  and 3cm +
oval;nearly round +
0.3 cm3 mm <br />0.003 m <br /> (3 cm30 mm <br />0.03 m <br />) +
3 +  and 8 +
inconspicuous +
enlarged +
not stoloniferous +  and 1-stemmed +
perennial +, short-lived +, biennial +  and annual +
biennial +, annual +  and perennial +
herb +  and matted +