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three-vein fleabane, threenerve fleabane

Alberta fleabane, three-lobed daisy

Habit Perennials, 15–90 cm; rhizomatous to subrhizomatous, fibrous-rooted, caudices usually branched, woody, thick. Perennials, 3–8(–10) cm; taprooted, caudex branches rhizomelike, relatively thick to thin, woody.
Stems

erect, moderately to densely hirsute (hairs 0.5–0.8 mm), eglandular.

mostly erect, hispido-hirsute, sometimes woolly distally, minutely glandular.

Leaves

basal (usually withering by flowering) and cauline;

basal blades oblanceolate-spatulate, 30–80 × 6–20(–27) mm, margins entire, faces evenly hirsute to strigoso-hirsute, usually eglandular;

cauline blades lanceolate to oblong, oblong-ovate, or broadly ovate, nearly even-sized distally or sometimes mid largest (continuing to immediately proximal to heads, bases clasping to subclasping).

basal (persistent);

blades spatulate to obovate-spatulate, 8–30 × 3–6 mm, margins usually 3-lobed, sometimes 2-lobed or entire (lobes 3–8 mm, lanceolate to narrowly ovate or oblong, apices usually acute), ultimately entire, coarsely ciliate, faces hirsute, minutely glandular.

Involucres

6–9 × 13–20 mm.

8–12 × 10–15 mm.

Ray florets

100–150;

corollas blue to lavender, 7–18 mm (ca. 1 mm wide), laminae coiling at tips.

20–40;

corollas white to pinkish, 10–15 mm, laminae not coiling or reflexing.

Disc corollas

4–5 mm.

3.5–4.5 mm.

Phyllaries

in 2–3(–4) series, moderately to densely hirsute, minutely glandular.

in 2–3 series (purplish or purple-tipped), hirsute to villoso-hirsute, glandular.

Heads

1–6(–21) in corymbiform arrays.

1.

Cypselae

1.6–2 mm, 2(–4)-nerved, faces sparsely strigose;

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

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

pappi: outer of setae, inner of 15–20 bristles (not twisted).

2n

= 45.

Erigeron subtrinervis

Erigeron trifidus

Phenology Flowering (Jun–)Jul–Sep. Flowering Jul–Aug.
Habitat Opening and margins, roadsides, often shaded, ponderosa pine, pine-fir, mixed conifer, aspen Dry talus and scree slopes in upper alpine zone
Elevation 1800–3000(–3500) m (5900–9800(–11500) ft) ca. 2600–3400 m (ca. 8500–11200 ft)
Distribution
from FNA
CO; ID; MT; ND; NE; NM; SD; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AB; BC
[BONAP county map]
Discussion

Erigeron subtrinervis is variable in vestiture, perhaps reflecting gene exchange with E. speciosus. Erigeron speciosus var. mollis (A. Gray) S. L. Welsh may be a recurrent hybrid; it is identified here within E. subtrinervis.

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

Erigeron trifidus has been treated as a synonym of E. compositus; caudex branches of the latter usually are relatively thick and short, compared to those of E. trifidus, which are thinner and are not covered with persistent leaf bases. Leaves of E. trifidus are consistently 3-lobed. Erigeron trifidus was hypothesized (J. G. Packer 1983) to be of hybrid origin (based on its polyploid chromosome number and sterile pollen), with E. lanatus and E. compositus as the most likely parents (based on intermediate morphology and sympatry of the putative parents).

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

Source FNA vol. 20, p. 330. FNA vol. 20, p. 301.
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. 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. 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. tenellus, E. tener, E. tenuis, E. tracyi, 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. glabellus var. mollis, E. speciosus var. mollis E. compositus var. trifidus
Name authority Rydberg ex Porter & Britton: Mem. Torrey Bot. Club 5: 328. (1894) Hooker: Fl. Bor.-Amer. 2: 17, plate 120. (1834)
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