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Big Horn fleabane

Rio Grande fleabane

Habit Perennials, 10–18 cm; taprooted, caudices multicipital or branched. Annuals, 15–40 cm; slenderly taprooted.
Stems

erect to ascending (branched, brittle), hispido-hirsute (hairs brittle), minutely glandular.

initially erect, later ascending to decumbent (herbaceous), proximally spreading- to deflexed-villous, closely to loosely strigose on distal 1/3–1/2, eglandular.

Leaves

basal (often not persistent) and cauline;

blades spatulate 15–30 × 1.5–4 mm, cauline gradually reduced distally (reduced to bracts on peduncles), margins usually 3-lobed (lobes linear to oblong-oblanceolate, about as wide as central portion of blades), sometimes 2-ternate or (cauline) entire, faces sparsely hispido-hirsute, minutely glandular.

basal (often drying translucent, often withering by flowering) and cauline;

basal (thin) blades oblanceolate to obovate or spatulate, 10–80(–140) × 5–34 mm, cauline slightly or gradually reduced to distal 1/3 of stems (bases clasping), margins usually with 1–4 pairs of teeth or lobes, sometimes entire, faces sparsely short-hirsute to hirsuto-villous, eglandular.

Involucres

4–5 × 6–9 mm.

2.5–3 × 5–10 mm.

Ray florets

20–40;

corollas white to bluish, sometimes drying pink, 3–6 mm, laminae not coiling or reflexing.

95–160(–250);

corollas white to bluish, 2.5–4 mm, laminae not coiling or reflexing.

Disc corollas

2.5–3.5 mm.

1.7–2 mm.

Phyllaries

in 2–3 series, glabrous or sometimes sparsely hispid, densely minutely glandular.

in 2–4 series, hirsute to sparsely villous, minutely glandular.

Heads

usually 2–4.

(1–)3–10(–20) in diffuse arrays (branches from distal 2/3).

Cypselae

2–2.3 mm, 2-nerved, faces sparsely strigose;

pappi: outer of setae, inner of 12–20 bristles.

0.6–0.8 mm, 2-nerved, faces sparsely strigose;

pappi: outer of setae, inner of 10–13(–15) bristles.

2n

= 18.

Erigeron allocotus

Erigeron tenellus

Phenology Flowering May–Aug. Flowering Feb–May.
Habitat Dry, calcareous sites on cliff faces, ledges, talus slopes, ridgetops, rock outcrops, barren redbeds, sometimes with Utah juniper, mountain mahogany, or sagebrush Brushlands, palm woods, roadsides, disturbed sites
Elevation 1300–2300 m (4300–7500 ft) 0–50 m (0–200 ft)
Distribution
from FNA
MT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico (Nuevo León, Tamaulipas)
[BONAP county map]
Discussion

The brittle, hispid vestiture, and multiple small heads (more than one per stem) with short rays of Erigeron allocotus are unusual among its putative relatives with 3-parted leaves.

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

Source FNA vol. 20, p. 299. FNA vol. 20, p. 319.
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. 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. 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. serpentinus, E. sionis, E. sivinskii, E. sparsifolius, E. speciosus, E. strigosus, E. subglaber, E. subtrinervis, E. supplex, 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
Name authority S. F. Blake: J. Wash. Acad. Sci. 27: 379. (1937) de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 288. (1836)
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