Dieteria canescens

(Pursh) Nuttall

Trans. Amer. Philos. Soc., n. s. 7: 300. 1840.

Common names: Hoary-aster
Illustrated
Basionym: Aster canescens Pursh Fl. Amer. Sept. 2: 547. 1813
Synonyms: Machaeranthera canescens (Pursh) A. Gray
Treatment appears in FNA Volume 20. Treatment on page 398. Mentioned on page 396.

Annuals, biennials, or short-lived perennials, (subshrubs in var. ziegleri). Stems, branches, and peduncles glabrous, puberulent, or canescent, sometimes also stipitate-glandular or gland-dotted. Leaf-blades linear-lanceolate to linear or linear-oblanceolate (ovate to obovate in var. leucanthemifolia), mid 10–60 × 1.5–6 (–8) mm, margins entire to irregularly dentate or serrate, faces glabrous, puberulent, or canescent, sometimes sparsely stipitate-glandular; distal bases not clasping or slightly clasping (clasping in var. leucanthemifolia). Involucres campanulate or turbinate. Phyllaries in 3–10 series, appressed, spreading, or reflexed, indurate bases usually glabrous, apices acute to acuminate, 1–3 mm, herbaceous, faces glabrous (indurate bases, sometimes foliaceous parts) or hairy (only foliaceous parts), sometimes stipitate-glandular. Receptacles 2.5–5 mm diam. Ray-florets pistillate and fertile, or sterile or 0 (in var. shastensis); laminae white, blue, or purple, 6–12 × 1–3 mm. Disc-florets: corollas 4–6 (–7) mm. Cypselae glabrous or moderately appressed-hairy.

Distribution

V20-909-distribution-map.gif

Alta., B.C., Sask., Ariz., Calif., Colo., Idaho, Kans., Mont., N.Dak., N.Mex., Nebr., Nev., Oreg., S.Dak., Tex., Utah, Wash., Wyo., nw Mexico

Discussion

Varieties 10 (10 in the flora).

Selected References

None.

Key

1 Phyllaries usually appressed, sometimes spreading, rarely reflexed > 2
1 Phyllaries spreading to reflexed, rarely appressed > 5
2 Ray florets sterile or 0 Dieteria canescens var. shastensis
2 Ray florets pistillate and fertile > 3
3 Phyllaries densely appressed-hairy, usually eglandular, sometimes sparsely stipitate-glandular, then obscured by appressed hairs Dieteria canescens var. ambigua
3 Phyllaries glabrous or stipitate-glandular, rarely appressed-hairy or canescent > 4
4 Stems stipitate-glandular, sometimes also canescent, rarely glabrous Dieteria canescens var. aristata
4 Stems glabrous, puberulent, or canescent, sometimes sparsely stipitate-glandular Dieteria canescens var. glabra
5 Involucres (9–)10–16 mm > 6
5 Involucres 6–10(–12) mm > 7
6 Subshrubs; involucres (10–)12–16 mm; phyllary apices densely stipitate-glandular Dieteria canescens var. ziegleri
6 Biennials or short-lived perennials; involucres (9–)10–15 mm; phyllary apices densely appressed-hairy, sometimes stipitate-glandular, then obscured by hairs Dieteria canescens var. nebraskana
7 Stems canescent, sometimes sparsely stipitate-glandular > 8
7 Stems stipitate-glandular, usually also puberulent or canescent, sometimes glabrous > 10
8 Stem usually 1, stiffly erect, branches widely divaricate, straight, stiff Dieteria canescens var. incana
8 Stems 1+, usually ascending, branches loosely spreading to ascending, not widely divaricate, curved, flexible > 9
9 Phyllaries in 5–10 series; ray florets pistillate and fertile Dieteria canescens var. canescens
9 Phyllaries in 3–5(–7) series; ray florets sterile or 0 Dieteria canescens var. shastensis
10 Stems canescent, usually gland-dotted; most peduncles 0 (heads sessile) or shorter than involucres Dieteria canescens var. sessiliflora
10 Stems stipitate-glandular, also sometimes puberulent or canescent; peduncles equaling or longer than involucres > 11
11 Mid and distal leaf blades ovate, oblong, or obovate, lengths 1.5–4 times widths Dieteria canescens var. leucanthemifolia
11 Mid and distal leaf blades linear-lanceolate to linear, lengths 4+ times widths Dieteria canescens var. aristata
... more about "Dieteria canescens"
not tailed +, rounded +  and obtuse +
distinct +
stipitate-glandular +  and hairy +
subequal +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
David R. Morgan +
(Pursh) Nuttall +
decurrent +
indurate +
Aster canescens +
linear;oblanceolate;linear;oblanceolate;lanceolate;oblong;obovate;ovate +
rugulose +  and muricate +
white +  and tawny +
Hoary-aster +
not 2-lipped +  and actinomorphic +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
yellow +, purple +, violet +, blue +  and white +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
8-12-ribbed +  and smooth +
beaked +, 2-ribbed +  and 5-ribbed +
appressed-hairy +  and glabrous +
flattened +, linear +  and obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
clasping +  and not clasping +
Alta. +, B.C. +, Sask. +, Ariz. +, Calif. +, Colo. +, Idaho +, Kans. +, Mont. +, N.Dak. +, N.Mex. +, Nebr. +, Nev. +, Oreg. +, S.Dak. +, Tex. +, Utah +, Wash. +, Wyo. +  and nw Mexico +
stipitate-glandular +, hairy +, glabrous +, canescent +  and puberulent +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.6 cm6 mm <br />0.006 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
turbinate;campanulate +
0.6 cm6 mm <br />0.006 m <br /> (3 cm30 mm <br />0.03 m <br />) +
purple +, blue +  and white +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
petiolate +  and sessile +
cauline +, proximal +  and basal +
deltate +  and lanceolate +
serrate +, entire +  and irregularly dentate +
2-carpellate +
persistent +
stipitate-glandular +, canescent +, puberulent +  and glabrous +
reflexed +, spreading +  and appressed +
lanceolate +  and linear +
Trans. Amer. Philos. Soc., n. s. +
sterile +  and fertile +
bearing subulate enations +, hairy +  and bristly +
exalbuminous +
Illustrated +
erect +  and ascending +
appendaged +  and truncate +
papillate +  and smooth +
Machaeranthera canescens +
Dieteria canescens +
Dieteria +
species +
perennial +, short-lived +, biennial +  and annual +
10 cm100 mm <br />0.1 m <br /> (100 cm1,000 mm <br />1 m <br />) +
tree +, shrub +  and subshrub +