Drymocallis hansenii

(Greene) Rydberg

Monogr. N. Amer. Potentilleae, 200. 1898.

Common names: Hansen’s drymocallis or wood beauty
Endemic
Basionym: Potentilla hansenii Greene Pittonia 3: 20. 1896 (as hanseni)
Synonyms: Drymocallis glandulosa subsp. hansenii (Greene) Soják P. glandulosa subsp. hansenii (Greene) D. D. Keck
Treatment appears in FNA Volume 9. Treatment on page 287. Mentioned on page 282, 283.

Caudex branches short-to-elongate. Stems usually solitary, sometimes loosely tufted, (3–) 4–9 dm; base (1–) 2–4 mm diam., moderately to densely septate-glandular. Leaves sparsely to moderately hairy; basal (7–) 10–25 (–30) cm, leaflet pairs 3–4; terminal leaflet broadly obovate, 2–5 (–6) × 1.5–3.5 (–4) cm, teeth single or double, 6–11 per side, apex usually rounded, sometimes obtuse; cauline 1–3, proximally well developed, leaflet pairs 2–4. Inflorescences 10–20 (–40) -flowered, not leafy, open, 1/4–2/3 of stem, narrow, branch angles 10–30°. Pedicels 2–8 (proximal to 20) mm, predominantly short-hairy, sparsely to moderately septate-glandular. Flowers opening widely; epicalyx bractlets linear to narrowly elliptic, 2–4 × 0.5–1 mm; sepals spreading, 5–8 mm, apex acute to acuminate; petals overlapping or not, spreading, cream-white to pale-yellow, broadly obovate, 4–6 × 3–6 mm, usually longer than, sometimes equal to, sepals; filaments 1.5–2.5 (–3) mm, anthers 0.8–1 mm; styles thickened, 0.8–1.2 mm. Achenes light-brown, 0.7–1 mm. 2n = 14.


Phenology: Flowering Jun–Sep.
Habitat: Moist ground, meadows, open forests, streamsides
Elevation: 1200–1900(–2200) m

Discussion

D. D. Keck (in J. Clausen et al. 1940) speculated that Drymocallis hansenii was the stabilized recombinant of D. glandulosa var. reflexa and D. lactea. Alternatively, it may represent the California counterpart of D. convallaria, because it tends to have tall, thick-based, single stems and narrow inflorescences. The species is centered in the west-central Sierra Nevada of California, usually occurring in moist meadows and equivalent habitats. Plants near Lake Tahoe, which provide the high-elevation extreme, combine the smaller stature of D. lactea and the glandular-septate stem bases of D. hansenii; their optimal taxonomic disposition is uncertain.

Selected References

None.

Lower Taxa

None.

"thin" is not a number."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 "Drymocallis hansenii"
light-brown +
0.7mm +  and 1mm +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
acute;acuminate +
Barbara Ertter +
(Greene) Rydberg +
compound +  and simple +
opposite +  and alternate +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
10 cm100 mm <br />0.1 m <br /> (25 cm250 mm <br />0.25 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Potentilla hansenii +
oblanceolate-oblong +
1 cm10 mm <br />0.01 m <br /> (25 cm250 mm <br />0.25 m <br />) +
coriaceous +
reduced +
free +  and distinct +
short +  and elongate +
Hansen’s drymocallis or wood beauty +
not +  and aggregated +
1200–1900(–2200) m +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
less;10;80 +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Moist ground, meadows, open forests, streamsides +
open +, not leafy +  and 10-20(-40)-flowered +
1/4 +  and 2/3 +
crassinucellate +
opposite +  and alternate +
marcescent +
winter-persistent +
overlapping +  and not confluent +
elliptic-ovate +  and flabellate or rhombic +
toothed +, or +, flat +, entire +  and more or less toothed +
inferior +  and superior +
clustered +, biseriate +  and superposed +
0.2 cm2 mm <br />0.002 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
not +  and overlapping +
0 (?) +  and 4 (?) +
cream-white +  and pale-yellow +
free +  and distinct +
obovate +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Flowering Jun–Sep. +
adnate +, free +, connate +  and distinct +
Monogr. N. Amer. Potentilleae, +
not arillate +
persistent +
free +  and distinct +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
free +  and distinct +
branched +  and simple +
stramineous +, reddish +  and green +
1 +  and 20 +
palmate +  and pinnate +
narrowly;broadly-triangular-ovate +
deciduous +
distinct +
fusiform +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
Drymocallis glandulosa subsp. hansenii +  and P. glandulosa subsp. hansenii +
Drymocallis hansenii +
Drymocallis +
species +
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 />) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
horseshoe--shaped +
6 (?) +  and 11 (?) +
inconspicuous +
hemispheric +  and conic +
enlarged +
peglike-glandular +  and septate-glandular +