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Hooker's fleabane, Huber's fleabane, tap-root fleabane

serpentine daisy, serpentine erigeron, serpentine fleabane

Habit Perennials, (1–)2–6(–12) cm; taprooted, caudices branches relatively short, thick. Perennials, 40–50 cm; taprooted, caudices simple.
Stems

erect, strigose to sparsely or densely short-villous (hairs loosely appressed to ascending or spreading), eglandular.

erect (arising from crowns, without axillary leaf tufts), glabrous or glabrate, eglandular.

Leaves

mostly basal (persistent) (eciliate or weakly ciliate proximally);

blades 1-nerved linear to narrowly oblanceolate or subspatulate, (5–)10–50(–60) × 0.8–2.5 mm (bases gradually narrowing), margins entire (apices obtuse to rounded), abaxial faces glabrate or glabrous, shiny, adaxial sparsely, loosely strigose, eglandular;

cauline mostly on proximal 1/2–1/3 of stems (absent in some high elevation forms), abruptly or gradually reduced distally.

mostly cauline;

blades linear, 20–40 × 0.6–0.8 mm (mid and distal longer than internodes), barely reduced distally, margins entire, ascending-ciliate (cilia thin-based), faces glabrous, eglandular.

Involucres

(3–)4–6(–8) × (5–)8–12(–15) mm.

4.5–5 × 9–12 mm.

Ray florets

(12–)20–44(–85);

corollas white, less commonly purplish, 4–7(–8) mm, laminae coiling.

9–13;

corollas white, drying blue, 7–8 mm, laminae weakly coiling.

Disc corollas

(2–)2.5–3.5(–4) mm.

3.2–4 mm (throats slightly indurate, not inflated).

Phyllaries

in 2–3(–4) series (subequal), villosulous to villoso-hirsutulous (hairs usually with purplish cross walls at least in basal cells), minutely glandular apically or eglandular.

in 3–5 series (inner: margins narrowly scarious), glabrate (barely perceptible), densely and minutely glandular.

Heads

1.

1 or 2–4 in loosely corymbiform arrays.

Cypselae

2.1–2.5 mm, 2-nerved, faces sparsely strigose;

pappi: outer of scales, inner of (6–)7–11 (readily falling) bristles.

(mature size not observed), 2-nerved, faces sparsely strigose;

pappi: outer of setae, inner of 26–32 bristles.

Erigeron radicatus

Erigeron serpentinus

Phenology Flowering May–Aug. Flowering May–Aug.
Habitat Rocky slopes, ridges, and summits, ledges and crevices, outcrops and talus, usually limestone, alpine tundra Shrubby vegetation over serpentine
Elevation (1400–)1600–2800(–3400) m ((4600–)5200–9200(–11200) ft) 400–600 m (1300–2000 ft)
Distribution
from FNA
CO; ID; MT; ND; NE; SD; UT; WY; AB; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Collections of Erigeron radicatus often have been identified as E. ochroleucus var. scribneri; E. radicatus is distinctive in its branched caudex, villous cauline vestiture, more reduced leaf vestiture, involucral vestiture of hairs with purple cross walls, shorter disc corollas, and relatively few, readily falling pappus bristles. Erigeron radicatus often is essentially scapiform at relatively high elevation (2700–3400 m) in Idaho, Montana, Utah, and Wyoming; more eastern populations in the Great Plains, at lower elevations (1400–2600 m), have leafier stems but are hardly different in other features. Plants of some populations in Albany and Carbon counties, Wyoming, produce atypically shorter rays.

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

Of conservation concern.

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

Source FNA vol. 20, p. 294. FNA vol. 20, p. 313.
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. poliospermus, E. porsildii, E. pringlei, E. procumbens, E. pulchellus, E. pulcherrimus, E. pumilus, E. purpuratus, E. pygmaeus, E. quercifolius, 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. 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. 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. 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
Synonyms E. huberi, E. macounii
Name authority Hooker: Fl. Bor.-Amer. 2: 17, plate 122. (1834) G. L. Nesom: Phytologia 72: 203. (1992)
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