Xanthisma grindelioides
Xanthisma coloradoense
goldenweed, gumweed aster, rayless tansyaster
10–30+, simple or branched in distal 1/3, moderately stout to stout, not wiry, hairy or minutely stipitate-glandular.
8–30+, simple, moderately stout to stout, not wiry, villous to pilose.
basal often persistent;
cauline evenly spaced, blades oblong, obovate, lanceolate to spatulate or narrowly ovate to obovate, 7–60 × 2–13 mm, gradually reduced distally, margins usually evenly coarsely serrate to serrulate, teeth 4–16 per side, each tipped with white bristle 0.5–4 mm, faces sparsely to densely hairy (hairs subappressed), often minutely stipitate-glandular.
basal persistent (similar to cauline);
cauline only a few pairs clustered with basal, absent distally, blades narrowly to broadly oblanceolate or spatulate, 10–80 × 3–10 mm, margins evenly to irregularly serrate or serrulate, teeth 3–14 per side, each tipped with white bristle 0.5–2 mm, faces sparsely to moderately hairy.
sparsely to densely hairy, often stipitate-glandular;
sometimes bracteate.
moderately to densely white-puberulent, eglandular; ebracteate.
hemispheric to campanulate, 0.5–1 × 0.6–1.5 cm.
depressed-hemispheric, 5–8 × 10–25 mm.
0.
20–35;
corollas pink to purple, tubes 2–3.5 mm, laminae 9.3–15 × 2.2–4.3 mm.
15–50+;
corollas 5–8.5 mm.
50–150+; 4.5–6.5 mm.
in 3–5 series, oblong to broadly lanceolate, 2–9 mm, apices obtuse to acute, tipped by white seta, faces usually densely stipitate-glandular.
in 3–4 series, broadly linear to lanceolate, 2.5–13 mm, apices acute to acuminate, tipped by white seta, faces moderately puberulent.
1–10+.
1.
oblong to narrowly obovoid, 2–3.5 mm, ribs 12–24, densely whitish to tawny hairy;
pappi whitish to tawny, 3–7 mm, a few abaxial bristles to 1/3 of longest.
narrowly obovoid to oblong, 1.7–3 mm, weakly 10–20-nerved or -ribbed, moderately to densely covered with whitish to tawny hairs;
pappi whitish to tawny, 3.5–6 mm, a few abaxial bristles to 1/3 of longest.
= 8, 16.
Xanthisma grindelioides
Xanthisma coloradoense
Varieties 2 (2 in the flora).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Xanthisma coloradoense is mostly alpine, but sometimes present in foothills or on plains, scattered through the southern Rocky Mountains of Colorado and southern Wyoming.
Xanthisma coloradoense and X. grindelioides var. grindelioides are known to hybridize in Carbon County, Wyoming, one of the few places where the two are sympatric. Several hybrid swarms have been detected in the vicinity of Wheatland Reservoir number 2.
Two varieties of Xanthisma coloradoense were recognized by R. L. Hartman (1976, 1990). They were distinguished by size, shape, and serration of leaves, size of flowering heads, and ray corolla length. With the number of additional collections amassed, these distinctions no longer hold and the varieties are not recognized.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Plants tufted, 10–35 cm; leaves evenly distributed along stems, margins usually ciliate, sometimes spinulose-dentate, bristles usually 0.5–1.5 mm; heads 1 or often 2–5; peduncles 0.5–2 cm, often bracteate to proximal to heads | var. grindeloides |
1. Plants densely cespitose, mostly 3–8 cm; leaves mostly crowded at base of stem, margins conspicuously white-bristled (1.5–)2–4 mm; heads usually 1; peduncles 1–4 cm, usually ebracteate | var. depressum |
CalFlora
PNW Herbaria
WildflowerSearch
iNaturalist
SW CO Wildflowers
USDA Plants Database
