Heterotheca grandiflora
Heterotheca monarchensis
silk-grass goldenaster, telegraph weed
Monarch goldenaster, sequoia false goldenaster
1–5+, ascending to erect (strict, 0.9–1.7 cm diam., only distal lateral branches developing in larger plants), moderately to densely hispido-strigose, more so proximally, moderately to densely stipitate-glandular, more so distally.
1–25+, ascending-erect, moderately to densely hispid.
basal and proximal cauline petiolate (petioles 3–7 cm, bases auriculate-clasping), blades ovate or elliptic to oblong, 50–80 × 20–30 mm, margins flat or somewhat undulate, coarsely serrate to serrulate or entire, proximally long-ciliate, apices acute, faces moderately to densely long-hispido-strigose;
distal sessile, blades oblong-lanceolate to lanceolate, 20–40 × 20–30 mm, reduced distally, margins often undulate, coarsely serrate.
proximal cauline petiolate, blades oblanceolate to obovate, 11–17(–25) × 2–3.7(–5) mm, bases cuneate, margins ± undulate, entire, strigoso-ciliate (proximal cilia long, spreading, numerous), apices acute, faces moderately to densely hispido-strigose, sparsely stipitate-glandular;
distal narrowly oblanceolate, little reduced distally.
10–65 mm, sparsely to densely hispido-strigose, densely stipitate-glandular;
bracts 0–3, linear-lanceolate to linear, reduced distally.
2–5(–10) mm, densely hispid, sparsely stipitate-glandular;
bracts leaflike, sometimes surpassing involucres, those subtending heads narrower than leaves.
campanulo-hemispheric, 6–9 mm.
cylindro-turbinate (campanulate upon drying), 6–7.5(–8.5) mm.
20–40;
laminae 5–8 × 1–2 mm.
(8–)12–16(–19);
laminae 10–14 × 1–2 mm.
30–75;
corollas 4–6 mm, lobes 0.5–0.8 mm.
30–45;
corollas ± ampliate, 5–6 mm, tubes sparsely pilose distally, lobes 0.45–0.7 mm, sparsely pilose (hairs 0.2–0.6 mm).
in 4–6 series, linear-lanceolate, unequal, margins scarious, faces strigose, densely stipitate-glandular.
in 3–4 series, unequal (outer lengths 1/4–1/2 inner), margins scarious, faces moderately strigose, sparsely stipitate-glandular.
10–110+, in corymbiform arrays, becoming paniculiform with age, branches ascending, usually relatively short compared to plant height.
1–2(–5), borne singly or in corymbiform arrays, branches ascending.
dimorphic, (ray) 2–5 mm, faces glabrous or slightly strigose on angles, (disc) 4–6 mm, faces moderately to densely strigose;
pappi 0 (ray) or (disc) stramineous to rusty brown, outer bristles 0.4–0.7 mm, inner 6–9 mm, longest weakly clavate.
monomorphic, obconic, somewhat compressed, 2–3 mm, ribs 9–11, shallow, faces moderately strigose;
pappi off-white, outer of linear scales 0.25–0.5 mm, inner of 25–40 bristles 5–6.5 mm, longest weakly clavate.
= 18.
= 18.
Heterotheca grandiflora
Heterotheca monarchensis
Heterotheca grandiflora is common in California, rare and probably introduced in Arizona, Nevada, and Utah, and introduced in Hawaii. Rosette plants can bloom in the spring.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Of conservation concern.
Heterotheca monarchensis grows only in Kings River Canyon, northeastern Fresno County. It can be superficially similar to densely hairy specimens of H. sessiliflora var. bolanderioides and to individuals of subsp. sessiliflora that are silvery white, but those usually have ovate-lanceolate distal cauline leaves, while H. monarchensis has oblanceolate ones. All three can have heads partially surrounded by distal leaves and long, subtending, leaflike bracts. Their ranges do not overlap, however. Specimens of H. monarchensis can be confused with H. villosa varieties; the latter lack the long, thin corolla hairs. The species has a small number of known populations and is therefore of conservation concern.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
