Chaenactis douglasii var. douglasii

Common names: False yarrow
IllustratedEndemic
Synonyms: Chaenactis angustifolia Greene Chaenactis douglasii var. achilleifolia Cronquist Chaenactis douglasii var. glandulosa M. E. Jones Chaenactis douglasii var. montana (Rydberg) Ferris Chaenactis douglasii var. rubricaulis Chaenactis pedicularia Chaenactis pumila Chaenactis ramosa
Treatment appears in FNA Volume 21. Mentioned on page 405, 407.

Biennials or perennials, (3–) 8–50 (–60) cm (sometimes slightly woody or flowering first-year, not or scarcely cespitose, not matted). Stems usually 1–5 (–12). Leaves basal (sometimes withering) and ± cauline, 1.5–12 (–15) cm, indument ± persistent. Heads (1–) 2–25+ per stem. Phyllaries: longest 9–15 (–17) mm; outer ± stipitate-glandular and, often, arachnoid to lanuginose and, sometimes, sparsely villous. 2n = 12, 24, 36 (plus dysploid numbers and triploids).


Phenology: Flowering May–Sep.
Habitat: Open sandy, gravelly, or rocky substrates in shrublands, woodlands, forests, often unstable or recently disturbed sites
Elevation: 400–3500 m

Distribution

V21-1020-distribution-map.gif

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

Discussion

Variety douglasii is known in and east of the Sierra Nevada and Cascade Ranges, to the western edge of the northern Great Plains, and in the Klamath Ranges and North Coast Ranges of northwestern California (where its lowest elevations occur). It is known from most mountains within that range; northward it also descends to the higher plains and valley floors. A report of var. douglasii from Saskatchewan was not verified by me. Seeds of var. douglasii are commercially available and are planted for revegetation or horticultural purposes and it may be found outside its native range.

Four ploidy levels were documented across the range of var. douglasii by J. S. Mooring (1965, 1980) and P. H. Raven and D. W. Kyhos (1961). Mooring’s (1980) data suggested that diploids are more frequent at higher elevations in major mountain chains and are more often mixed with polyploids at lower elevations or in areas of Pleistocene or later disturbance. The chromosome numbers listed above are predominant; Mooring (1965, 1980, 1992) also documented 2n = 14, 15, 26, or 30 as regular bivalents. Additional numbers, involving various combinations of bivalents with univalents, tetravalents, and/or extra chromosomes, have been observed.

Most of the diploid elements of var. douglasii are distinctive and are connected by a morphologically continuous series of polyploids (usually assigned to var. achilleifolia). Some diploid forms (including var. rubricaulis and Chaenactis ramosa) appear repeatedly and discontinuously in suitable habitats. In particular, forms named var. montana seem to arise wherever the species reaches sufficient elevation. Such populations have no historic or genetic cohesion to justify their recognition as a collective taxon, even though their reduced stature may become genetically fixed in each instance. (Variety alpina, recognized below with hesitation, may be just an extreme such case.) Chaenactis angustifolia of the northern Rocky Mountains and possibly C. pedicularia of Colorado are more distinctive morphologically and geographically, and merit further study and possible varietal status.

Lower Taxa

None.

"longest" is not a number.

36 +, 24 +  and 12 +
not tailed +, rounded +  and obtuse +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
paniculiform +, cymiform +  and corymbiform +
indeterminate +  and determinate +
James D. Morefield +
(Hooker) Hooker & Arnott +
decurrent +
Hymenopappus douglasii +
compound +  and simple +
lobed;ovate;oblanceolate;ovate;oblanceolate;linear;deltate +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
connate +  and distinct +
False yarrow +
actinomorphic +
white +  and pinkish or cream +
stipitate-glandular +  and hairy +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
fertile +  and bisexual +
fertile +  and bisexual +
Alta. +, B.C. +, Ariz. +, Calif. +, Colo. +, Idaho +, Mont. +, Nev. +, N.Mex. +, N.Dak. +, Oreg. +, S.Dak. +, Utah +, Wash. +  and Wyo. +
400–3500 m +
strigose +  and densely sericeous +
scabrellous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
campanulate +  and cylindric +
Open sandy, gravelly, or rocky substrates in shrublands, woodlands, forests, often unstable or recently disturbed sites +
in more or less cymiform arrays +, singly +  and radiant +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
obconic;more or less hemispheric +
lobed +, less elliptic or slightly lanceolate +  and ovate +
12 cm120 mm <br />0.12 m <br /> (15 cm150 mm <br />0.15 m <br />) +
cauline +  and basal +
1.5 cm15 mm <br />0.015 m <br /> (?) +  and 12 cm120 mm <br />0.12 m <br /> (?) +
deltate +  and more or less lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
dentate to pinnatifid or palmatifid +  and entire +
villous +, arachnoid +  and lanuginose +
2-carpellate +
persistent +
coroniform +
1 cm10 mm <br />0.01 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Flowering May–Sep. +
1.5 cm15 mm <br />0.015 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
5 +  and 21 +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
mostly arachnoid-sericeous +  and thinly lanuginose +
Bot. Beechey Voy., +
bearing subulate enations +, hairy +  and bristly +
knobby;convex;more or less flat +
mooring1980a +
distinct +
10 +  and 20 +
exalbuminous +
unequal +
Illustrated +  and Endemic +
5 (?) +  and 12 (?) +
erect +  and spreading +
1 +  and 5 +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Chaenactis angustifolia +, Chaenactis douglasii var. achilleifolia +, Chaenactis douglasii var. glandulosa +, Chaenactis douglasii var. montana +, Chaenactis douglasii var. rubricaulis +, Chaenactis pedicularia +, Chaenactis pumila +  and Chaenactis ramosa +
Chaenactis douglasii var. douglasii +
Chaenactis douglasii +
variety +
cylindric +
80 cm800 mm <br />0.8 m <br /> (300 cm3,000 mm <br />3 m <br />) +
1 cm10 mm <br />0.01 m <br /> (80 cm800 mm <br />0.8 m <br />) +
toothed +  and entire +
50 cm500 mm <br />0.5 m <br /> (60 cm600 mm <br />0.6 m <br />) +
perennial +  and biennial +
8 cm80 mm <br />0.08 m <br /> (50 cm500 mm <br />0.5 m <br />) +