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Erigeron oreganus

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

arid throne fleabane, dry-sun fleabane

Habit Perennials, 5–15 cm; stoutly taprooted, caudices usually simple. Annuals or short-lived perennials, 30–70 cm; taprooted.
Stems

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

erect, coarsely hirsute to hispid (hairs only along ribs, bases thickened), minutely glandular.

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).

mostly cauline;

blades linear to linear-oblong, -lanceolate, or -oblanceolate (slightly narrowed distally), 25–50 × 2–5 mm, margins entire or sometimes lobed (lobes 1–2 pairs, coarse, rounded), faces hispido-strigose.

Involucres

5–7 × 9–13 mm.

2.5–3.5 × 5–8 mm.

Ray florets

30–60;

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

125–180;

corollas usually white, sometimes lavender or pinkish, 6–7 mm, laminae reflexing.

Disc corollas

3.4–4.7 mm.

2–2.5 mm (throats indurate and inflated).

Phyllaries

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

in 3–4 series, minutely hispid, minutely glandular.

Heads

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

20–50+ in loose, corymbiform arrays (buds erect).

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).

0.7–1 mm, 2-nerved (nerves orange), faces sparsely strigose to glabrate;

pappi: outer of setae or lanceolate scales, inner of (10–)12–17 bristles.

2n

= 18.

Erigeron oreganus

Erigeron arisolius

Phenology Flowering May–Sep. Flowering May–Jun(–Nov).
Habitat Moist shady cliffs and ledges Grasslands, often in moist areas, sometimes with mesquite, openings, roadsides, oak, juniper, mesquite
Elevation 20–400 m (100–1300 ft) (800–)1300–1700 m ((2600–)4300–5600 ft)
Distribution
from FNA
OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; Mexico (Sonora)
[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.)

Of conservation concern.

Erigeron arisolius is similar in general appearance to E. divergens; the erect buds and reflexing rays of E. arisolius contrast with the nodding buds and non-reflexing rays of E. divergens. Additionally, the latter has evenly distributed stem pubescence, cypselae with whitish nerves (versus orange), and fewer pappus bristles. Erigeron sceptrifer also may be difficult to distinguish from these: it is more similar to E. arisolius in vestiture and has shorter rays that usually become purple upon drying and that are downward-curved, compared to those of E. arisolius, where the rays dry a lighter color and reflex at the tube-lamina junction.

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

Source FNA vol. 20, p. 284. FNA vol. 20, p. 337.
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. annuus, E. aphanactis, E. arenarioides, E. argentatus, 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
Name authority A. Gray: Proc. Amer. Acad. Arts 19: 2. (1883) G. L. Nesom: Phytologia 69: 243. (1990)
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