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buff daisy, cushion daisy, cushion fleabane, hairy-seed daisy, hairy-seed fleabane, Kittitas fleabane, purple-cushion fleabane

arid throne fleabane, dry-sun fleabane

Habit Perennials, 3–15 cm; taprooted, caudices simple or with relatively short and thick branches. Annuals or short-lived perennials, 30–70 cm; taprooted.
Stems

erect, sometimes branched, hirsute (hairs unequal), ± minutely glandular.

erect, coarsely hirsute to hispid (hairs only along ribs, bases thickened), minutely glandular.

Leaves

mostly basal (persistent; petioles prominently ciliate, hairs spreading, thick-based);

blades narrowly oblanceolate to spatulate, (20–)30–80 × 2–4(–12) mm, cauline sometimes continuing distally to about midstem, margins entire, usually ciliate, sometimes coarsely so, faces sparsely to densely hirsute, sometimes minutely glandular.

mostly cauline;

blades linear to linear-oblong, -lanceolate, or -oblanceolate (slightly narrowed distally), 25–50 × 2–5 mm, margins entire or sometimes lobed (lobes 1–2 pairs, coarse, rounded), faces hispido-strigose.

Involucres

5–9 × 9–20 mm.

2.5–3.5 × 5–8 mm.

Ray florets

15–45 or 0;

corollas usually pink to bluish purple, sometimes white, 5–14 mm, laminae coiling.

125–180;

corollas usually white, sometimes lavender or pinkish, 6–7 mm, laminae reflexing.

Disc corollas

(3.5–)4–5.5 mm.

2–2.5 mm (throats indurate and inflated).

Phyllaries

in 2–3 series, sparsely to densely hirsuto-villous to hirsute, minutely glandular.

in 3–4 series, minutely hispid, minutely glandular.

Heads

1(–3) (from branches at or proximal to midstem).

20–50+ in loose, corymbiform arrays (buds erect).

Cypselae

2.5–3 mm, 2-nerved, faces densely strigoso-sericeous (obscured);

pappi: outer of setae, inner of 20–30 bristles.

0.7–1 mm, 2-nerved (nerves orange), faces sparsely strigose to glabrate;

pappi: outer of setae or lanceolate scales, inner of (10–)12–17 bristles.

2n

= 18.

Erigeron poliospermus

Erigeron arisolius

Phenology Flowering May–Jun(–Nov).
Habitat Grasslands, often in moist areas, sometimes with mesquite, openings, roadsides, oak, juniper, mesquite
Elevation (800–)1300–1700 m ((2600–)4300–5600 ft)
Distribution
from FNA
ID; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; Mexico (Sonora)
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

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

Of conservation concern.

Erigeron arisolius is similar in general appearance to E. divergens; the erect buds and reflexing rays of E. arisolius contrast with the nodding buds and non-reflexing rays of E. divergens. Additionally, the latter has evenly distributed stem pubescence, cypselae with whitish nerves (versus orange), and fewer pappus bristles. Erigeron sceptrifer also may be difficult to distinguish from these: it is more similar to E. arisolius in vestiture and has shorter rays that usually become purple upon drying and that are downward-curved, compared to those of E. arisolius, where the rays dry a lighter color and reflex at the tube-lamina junction.

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

Key
1. Stems branched at or proximal to midstem; basal leaves and branches originating on elongate internodes from proximal 1–6 cm of primary stems; stems and involucres glabrous or sparsely hirsute, densely minutely glandular
var. cereus
1. Stems simple; basal leaves and stems originating from compressed nodes at caudex apices; stems and involucres densely hirsute, sparsely minutely glandular
→ 2
2. Rays 0
var. disciformis
2. Rays 15–45
var. poliospermus
Source FNA vol. 20, p. 285. FNA vol. 20, p. 337.
Parent taxa Asteraceae > tribe Astereae > Erigeron Asteraceae > tribe Astereae > Erigeron
Sibling taxa
E. abajoensis, E. acomanus, E. acris, E. aequifolius, E. algidus, E. aliceae, E. allocotus, E. alpiniformis, E. anchana, E. annuus, E. aphanactis, E. arenarioides, E. argentatus, E. arisolius, E. arizonicus, E. asperugineus, E. aureus, E. barbellulatus, E. basalticus, E. bellidiastrum, E. bigelovii, E. biolettii, E. blochmaniae, E. bloomeri, E. breweri, E. caespitosus, E. calvus, E. canaani, E. canus, E. cascadensis, E. cavernensis, E. cervinus, E. chrysopsidis, E. clokeyi, E. compactus, E. compositus, E. concinnus, E. consimilis, E. corymbosus, E. coulteri, E. cronquistii, E. davisii, E. decumbens, E. denalii, E. disparipilus, E. divergens, E. eatonii, E. elatior, E. elatus, E. elegantulus, E. elmeri, E. engelmannii, E. evermannii, E. eximius, E. filifolius, E. flabellifolius, E. flagellaris, E. flettii, E. foliosus, E. formosissimus, E. garrettii, E. geiseri, E. glabellus, E. glacialis, E. glaucus, E. goodrichii, E. gracilis, E. grandiflorus, E. greenei, E. heliographis, E. hessii, E. howellii, E. humilis, E. hyperboreus, E. hyssopifolius, E. inornatus, E. jonesii, E. kachinensis, E. karvinskianus, E. klamathensis, E. kuschei, E. lackschewitzii, E. lanatus, E. lassenianus, E. latus, E. leibergii, E. leiomerus, E. lemmonii, E. linearis, E. lobatus, E. lonchophyllus, E. maguirei, E. mancus, E. maniopotamicus, E. mariposanus, E. melanocephalus, E. miser, E. modestus, E. muirii, E. multiceps, E. nanus, E. nauseosus, E. nematophyllus, E. neomexicanus, E. nivalis, E. ochroleucus, E. oreganus, E. oreophilus, E. ovinus, E. oxyphyllus, E. pallens, E. parishii, E. parryi, E. peregrinus, E. petrophilus, E. philadelphicus, E. pinnatisectus, E. piperianus, E. piscaticus, E. porsildii, E. pringlei, E. procumbens, E. pulchellus, E. pulcherrimus, E. pumilus, E. purpuratus, E. pygmaeus, E. quercifolius, E. radicatus, E. reductus, E. religiosus, E. rhizomatus, E. robustior, E. rybius, E. rydbergii, E. salishii, E. salmonensis, E. sanctarum, E. saxatilis, E. sceptrifer, E. scopulinus, E. serpentinus, E. sionis, E. sivinskii, E. sparsifolius, E. speciosus, E. strigosus, E. subglaber, E. subtrinervis, E. supplex, E. tenellus, E. tener, E. tenuis, E. tracyi, E. trifidus, E. tweedyi, E. uintahensis, E. uncialis, E. uniflorus, E. untermannii, E. ursinus, E. utahensis, E. vagus, E. velutipes, E. vernus, E. versicolor, E. vetensis, E. vicinus, E. vreelandii, E. watsonii, E. wilkenii, E. yukonensis
E. abajoensis, E. acomanus, E. acris, E. aequifolius, E. algidus, E. aliceae, E. allocotus, E. alpiniformis, E. anchana, E. annuus, E. aphanactis, E. arenarioides, E. argentatus, E. arizonicus, E. asperugineus, E. aureus, E. barbellulatus, E. basalticus, E. bellidiastrum, E. bigelovii, E. biolettii, E. blochmaniae, E. bloomeri, E. breweri, E. caespitosus, E. calvus, E. canaani, E. canus, E. cascadensis, E. cavernensis, E. cervinus, E. chrysopsidis, E. clokeyi, E. compactus, E. compositus, E. concinnus, E. consimilis, E. corymbosus, E. coulteri, E. cronquistii, E. davisii, E. decumbens, E. denalii, E. disparipilus, E. divergens, E. eatonii, E. elatior, E. elatus, E. elegantulus, E. elmeri, E. engelmannii, E. evermannii, E. eximius, E. filifolius, E. flabellifolius, E. flagellaris, E. flettii, E. foliosus, E. formosissimus, E. garrettii, E. geiseri, E. glabellus, E. glacialis, E. glaucus, E. goodrichii, E. gracilis, E. grandiflorus, E. greenei, E. heliographis, E. hessii, E. howellii, E. humilis, E. hyperboreus, E. hyssopifolius, E. inornatus, E. jonesii, E. kachinensis, E. karvinskianus, E. klamathensis, E. kuschei, E. lackschewitzii, E. lanatus, E. lassenianus, E. latus, E. leibergii, E. leiomerus, E. lemmonii, E. linearis, E. lobatus, E. lonchophyllus, E. maguirei, E. mancus, E. maniopotamicus, E. mariposanus, E. melanocephalus, E. miser, E. modestus, E. muirii, E. multiceps, E. nanus, E. nauseosus, E. nematophyllus, E. neomexicanus, E. nivalis, E. ochroleucus, E. oreganus, E. oreophilus, E. ovinus, E. oxyphyllus, E. pallens, E. parishii, E. parryi, E. peregrinus, E. petrophilus, E. philadelphicus, E. pinnatisectus, E. piperianus, E. piscaticus, E. poliospermus, E. porsildii, E. pringlei, E. procumbens, E. pulchellus, E. pulcherrimus, E. pumilus, E. purpuratus, E. pygmaeus, E. quercifolius, E. radicatus, E. reductus, E. religiosus, E. rhizomatus, E. robustior, E. rybius, E. rydbergii, E. salishii, E. salmonensis, E. sanctarum, E. saxatilis, E. sceptrifer, E. scopulinus, E. serpentinus, E. sionis, E. sivinskii, E. sparsifolius, E. speciosus, E. strigosus, E. subglaber, E. subtrinervis, E. supplex, E. tenellus, E. tener, E. tenuis, E. tracyi, E. trifidus, E. tweedyi, E. uintahensis, E. uncialis, E. uniflorus, E. untermannii, E. ursinus, E. utahensis, E. vagus, E. velutipes, E. vernus, E. versicolor, E. vetensis, E. vicinus, E. vreelandii, E. watsonii, E. wilkenii, E. yukonensis
Subordinate taxa
E. poliospermus var. cereus, E. poliospermus var. disciformis, E. poliospermus var. poliospermus
Name authority A. Gray: in A. Gray et al., Syn. Fl. N. Amer. 1(2): 210. (1884) G. L. Nesom: Phytologia 69: 243. (1990)
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