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Idaho daisy, Idaho fleabane

Peck's threadleaf fleabane, thread-leaf daisy, thread-leaf fleabane

Habit Perennials, 2–20 cm; slenderly taprooted, caudices usually branched. Perennials, 10–30(–50) cm; taprooted, caudices multicipital, often with relatively short and thin, stemlike, lignescent branches.
Stems

usually decumbent-ascending, moderately to densely hirsutulous to hirtellous (hairs usually deflexed), eglandular.

erect, sparsely to densely strigose (hairs loosely appressed to ascending, fine), densely white-strigose at least proximally, eglandular.

Leaves

basal (persistent) and cauline;

basal blades 1-nerved or weakly 3-nerved, spatulate, rhombic-elliptic to obovate or oblanceolate (often folding), 20–50(–80) × 3–10(–13) mm;

cauline gradually or abruptly reduced and linear distally (bases abruptly contracted to petioles), margins entire, faces moderately to densely hirsutulous, eglandular.

basal (usually persistent, not clustered as rosettes) and cauline;

basal blades linear to filiform, 10–80 × 0.5–2.5(–3.5) mm;

cauline gradually or little reduced distally, margins entire, faces sparsely to moderately strigose, eglandular.

Involucres

5–9 × 7–14 mm.

4–7 × 5–-18 mm.

Ray florets

10–25;

corollas deep blue or violet to rose-purple, 5–10 mm, laminae not coiling or reflexing.

(15–)20–125;

corollas usually blue, sometimes white, pink, or pale lavender, 3–13 mm, laminae coiling.

Disc corollas

4.2–6.3 mm.

2.5–5.5 mm.

Phyllaries

in 3–4 series (tips and margins often purple), sparsely to moderately hirsutulous, densely minutely glandular.

in (2–)3–4 series, loosely strigose to hirsute or nearly villous, densely to sparsely minutely glandular.

Heads

1(–2).

1–5(–10+) from distal branches, tending to be in corymbiform arrays.

Cypselae

2.5–3.1 mm, 2-nerved, faces sparsely strigose;

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

1.4–1.8(–2) mm, 2-nerved, faces sparsely strigose to glabrate;

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

2n

= 18.

Erigeron asperugineus

Erigeron filifolius

Phenology Flowering Jul–Aug. Flowering May–Aug.
Habitat Rocky or gravelly slopes and ridges, talus, sagebrush or meadow edges, limber pine, whitebark pine, fir-pine Dry, rocky or sandy soil, lava beds, bitterbrush, sagebrush, juniper, ponderosa pine
Elevation (2100–)2500–3300 m ((6900–)8200–10800 ft) 400–2400 m (1300–7900 ft)
Distribution
from FNA
ID; MT; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; ID; MT; NV; OR; UT; WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Erigeron asperugineus sometimes is very similar in aspect to E. clokeyi var. pinzliae; the latter differs in its narrower leaves, coarsely ciliate petioles, broader and non-reflexing rays, and shorter cypselae.

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

The densely white-strigose stem bases, linear-filiform leaves relatively unreduced distally, and relatively few heads with coiling, usually blue rays are distinctive for Erigeron filifolius. Proximal leaves are not clustered as a basal rosette; they are inserted on closely spaced nodes that are slightly more separated distally. Plants identified as var. robustior (with more ray florets, fewer heads, and thicker stems, centered in Oregon and Washington) intergrade with the typical form and apparently are separated arbitrarily.

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

Source FNA vol. 20, p. 306. FNA vol. 20, p. 298.
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. 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
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. 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
Synonyms Aster asperugineus Diplopappus filifolius, E. filifolius var. robustior
Name authority (D. C. Eaton) A. Gray: Notes Compositae, 91. (1880) (Hooker) Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 308. (1840)
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