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Erigeron oreganus

Columbia Gorge daisy, Columbia Gorge fleabane, Gorge daisy, Gorge fleabane, Oregon fleabane

annual daisy, annual fleabane, eastern daisy fleabane, sweet scabrous fleabane, vergerette annuelle

Habit Perennials, 5–15 cm; stoutly taprooted, caudices usually simple. Annuals, (10–)60–150 cm; fibrous-rooted or taprooted.
Stems

decumbent to basally ascending or erect, moderately villous, stipitate-glandular.

erect, sparsely piloso-hispid (hairs spreading), sometimes strigose distally, eglandular.

Leaves

basal (persistent) and cauline;

basal blades (1-nerved or weakly 3-nerved) obovate to spatulate, mostly 20–60(–100) × 5–15(–25) mm, margins usually coarsely dentate or incised, sometimes shallowly serrate, faces sparsely to moderately villous, stipitate-glandular;

cauline gradually or little reduced distally (bases not clasping).

basal (usually withering by flowering) and cauline;

basal blades mostly lanceolate to oblanceolate or ovate, 15–80 × 3–20 mm, margins coarsely serrate to nearly entire, faces sparsely strigoso-hirsute, eglandular;

cauline lanceolate to oblong, little reduced proximal to midstem.

Involucres

5–7 × 9–13 mm.

3–5 × 6–12 mm.

Ray florets

30–60;

corollas white to pink, 5–8 mm, laminae not coiling or reflexing.

80–125;

corollas white, 4–10 mm, laminae tardily coiling.

Disc corollas

3.4–4.7 mm.

2–2.8 mm.

Phyllaries

in 2–3 series, moderately villous, minutely stipitate-glandular.

in 2–3(–4) series, sparsely villous or hirsuto-villous, minutely glandular.

Heads

1(–4) (on branches from proximal axils).

ca. 5–50+ in loosely paniculiform or corymbiform arrays.

Cypselae

flattened, 1.2–1.4 mm, 2-nerved, faces sparsely strigose;

pappi: outer of setae, inner of 15–20 bristles (weakly barbellate and curled and twisted to at least distal 1/2).

0.8–1 mm, 2-nerved, faces sparsely strigose;

pappi: outer minute crowns of setae or narrow scales, inner 0 (rays) or of 8–11 bristles (disc).

2n

= 27.

Erigeron oreganus

Erigeron annuus

Phenology Flowering May–Sep. Flowering Jun–Aug(–Nov).
Habitat Moist shady cliffs and ledges Mostly open, disturbed habitats, especially roadsides, fields, waste areas
Elevation 20–400 m (100–1300 ft) 0–500(–2200) m (0–1600(–7200) ft)
Distribution
from FNA
OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CA; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; BC; MB; NB; NF; NS; ON; PE; QC; SK; SPM; Mexico (Hidalgo); Central America (Costa Rica, Nicaragua, Panama); Europe; Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

Erigeron oreganus grows in the Columbia River Gorge, primarily on the north side.

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

Erigeron annuus is apparently native to eastern North America (United States and southern Canada) and is introduced elsewhere; it probably occurs in North Dakota and Alberta; apparently it has not been documented there. Apparent intermediates between E. annuus and E. strigosus are encountered.

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

Source FNA vol. 20, p. 284. FNA vol. 20, p. 344.
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. 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. 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
Synonyms Aster annuus, E. annuus var. discoideus
Name authority A. Gray: Proc. Amer. Acad. Arts 19: 2. (1883) (Linnaeus) Persoon: Syn. Pl. 2: 431. (1807)
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