The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

chaenactis, Douglas' dusty maidens, Douglas' dustymaiden, hoary chaenactis, hoary false-yarrow, hoary pincushion

santolina chaenactis, santolina pincushion

Habit Biennials or perennials, (2–)5–50(–60) cm (rarely slightly woody or flowering first year, sometimes cespitose or ± matted); proximal indument thinning with age, grayish, mostly arachnoid-sericeous to thinly lanuginose. Perennials, 10–25(–35) cm (cespitose or ± matted); proximal indument thinning with age, whitish to grayish, lanuginose.
Stems

1–25+, erect to spreading.

mostly 5–15+, erect to ± spreading.

Leaves

basal, or basal (sometimes withering) and ± cauline, (1–)2–12(–15) cm;

largest blades ± elliptic or slightly lanceolate to ovate, ± 3-dimensional, usually 2-pinnately lobed;

primary lobes (4–)5–9(–12) pairs, ± congested, scarcely imbricate, ultimate lobes ± involute and/or twisted.

basal, (1–)3–11 cm;

largest blades linear-cylindric to ± fusiform, 3-dimensional, 1–2-pinnately lobed;

primary lobes (7–)10–18+ pairs, ± imbricate, ultimate lobes ± involute, twisted.

Peduncles

mostly ascending to erect, 1–10 cm.

mostly ascending to erect, mostly 8–25 cm.

Involucres

obconic to ± hemispheric.

obconic to ± cylindric.

Corollas

5–8 mm.

5–7 mm.

Phyllaries

longest 9–15(–17) mm;

outer usually stipitate-glandular (sometimes sparsely or obscurely, rarely eglandular) and, often, arachnoid to lanuginose and, sometimes, sparsely villous, apices usually ± squarrose, pliant.

longest 8–13 mm;

outer evidently stipitate-glandular and, sometimes, ± arachnoid, apices erect, ± rigid.

Heads

1–25+ per stem.

1(–3) per stem.

Cypselae

5–8 mm (usually sparsely glandular amidst other indument);

pappi: longest scales 3–6 mm.

4–6 mm;

pappi: longest scales 3–4.5 mm.

2n

= 12.

Chaenactis douglasii

Chaenactis santolinoides

Phenology Flowering (Mar–)May–Jul.
Habitat Exposed sandy to rocky summits, ridges, scree, talus, openings in or above conifer forests, sometimes road cuts or other recent disturbances
Elevation (1100–)1500–2800 m ((3600–)4900–9200 ft)
Distribution
from FNA
AZ; CA; CO; ID; MT; ND; NM; NV; OR; SD; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Chaenactis douglasii is widespread and variable (see discussion under var. douglasii).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Of conservation concern.

Chaenactis santolinoides is known from the southern Sierra Nevada and Transverse Ranges. It is sometimes cultivated in rock gardens and may be found beyond its native range. It may be relatively recently derived from an isolated segment of C. douglasii var. alpina. The morphology of C. panamintensis (here assigned to C. douglasii var. alpina) suggests past convergence toward, or genetic influence from, C. santolinoides.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaves basal (sometimes withering) and ± cauline; plants not or scarcely cespitose, not matted; stems usually 1–5(–12); heads (1–)2–25+ per stem
var. douglasii
1. Leaves strictly basal; plants cespitose or ± matted; stems (1–)10–25+; heads 1(–2) per stem
var. alpina
Source FNA vol. 21, p. 405. FNA vol. 21, p. 407.
Parent taxa Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Chaenactis > sect. Macrocarphus Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Chaenactis > sect. Macrocarphus
Sibling taxa
C. alpigena, C. artemisiifolia, C. carphoclinia, C. cusickii, C. evermannii, C. fremontii, C. glabriuscula, C. macrantha, C. nevadensis, C. nevii, C. parishii, C. santolinoides, C. stevioides, C. suffrutescens, C. thompsonii, C. xantiana
C. alpigena, C. artemisiifolia, C. carphoclinia, C. cusickii, C. douglasii, C. evermannii, C. fremontii, C. glabriuscula, C. macrantha, C. nevadensis, C. nevii, C. parishii, C. stevioides, C. suffrutescens, C. thompsonii, C. xantiana
Subordinate taxa
C. douglasii var. alpina, C. douglasii var. douglasii
Synonyms Hymenopappus douglasii, Macrocarphus douglasii
Name authority (Hooker) Hooker & Arnott: Bot. Beechey Voy., 354. (1839) Greene: Bull. Torrey Bot. Club 9: 17. (1882)
Web links