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Erigeron oreganus

Gorge daisy, gorge fleabane, Oregon fleabane

Philadelphia fleabane

Habit Plants perennial, 5–15 cm; taprooted, caudices unbranched. Plants annual, biennial, or short-lived perennial, 10–80 cm; roots fibrous, caudices usually simple.
Stems

decumbent to erect; hirsute with unequal hairs, sparsely glandular.

erect, sparsely to moderately hirsute to lanate, minutely glandular.

Basal leaves

persistent, obovate, 15–90 × 5–20 mm;

margins coarsely serrate to shallowly lobulate;

surfaces sparsely to moderately hirsute to strigose.

withering by flowering, oblanceolate to nearly spatulate, 20–170 × 5–35 mm;

margins nearly entire, coarsely serrate, lobulate, or shallowly dentate;

surfaces slightly to moderately strigose or hirsute, eglandular.

Cauline leaves

obovate to elliptic; little or not reduced distally;

surfaces sparsely to moderately hirsute.

oblanceolate to lanceolate to elliptic or oblong, 5–130 × 3–25 mm, distally reduced, bases clasping;

surfaces eglandular.

Involucres

4–7 × 9–15 mm.

3–6 × 6–15 mm.

Ray florets

30–60, pink to purple;

rays 4–5 × 0.5–1 mm.

150–250, white to pink;

rays 2–7 × 0.2–0.5 mm.

Disc florets

corollas 3–5 mm.

corollas 2–3 mm.

Phyllaries

in 2–3 series, pale green with dark green medial stripe;

surfaces remotely hirsute, strongly stipitate-glandular.

in 2–3 series;

surfaces sparsely to moderately hirsute, minutely glandular.

Fruits

2–3 mm, moderately strigose;

inner pappi of several unbarbed to weakly barbellate twisted bristles.

1–1.5 mm, sparsely to moderately strigose;

inner pappi of numerous barbellate bristles.

Heads

1–4, radiate.

(1)3–many in corymb-like arrays, radiate.

2n

=18.

Erigeron oreganus

Erigeron philadelphicus

Distribution
[WildflowerSearch map]
[BONAP county map]
[WildflowerSearch map]
[BONAP county map]
Discussion

Shady cliffs, rocky slopes, crevices. Flowering May–Aug. 100–400 m. Casc. WA. Native.

This uncommon species is found only in the Columbia River Gorge.

Disturbed areas, streambanks, fields, meadows, forest openings. Flowering Apr–Sep. 0–1900 m. All ecoregions. CA, ID, NV, WA; nearly worldwide. Native.

Source Flora of Oregon, volume 2, page 259
James Riser, Stephen Meyers
Flora of Oregon, volume 2, page 260
James Riser, Stephen Meyers
Sibling taxa
E. acris, E. aliceae, E. annuus, E. aphanactis, E. aureus, E. bloomeri, E. cascadensis, E. cervinus, E. chrysopsidis, E. compositus, E. corymbosus, E. coulteri, E. decumbens, E. disparipilus, E. divergens, E. eatonii, E. elegantulus, E. filifolius, E. foliosus, E. glacialis, E. glaucus, E. howellii, E. inornatus, E. karvinskianus, E. klamathensis, E. latus, E. linearis, E. lonchophyllus, E. nivalis, E. peregrinus, E. petrophilus, E. philadelphicus, E. poliospermus, E. pumilus, E. simplex, E. speciosus, E. stanselliae, E. strigosus, E. tener, E. vagus
E. acris, E. aliceae, E. annuus, E. aphanactis, E. aureus, E. bloomeri, E. cascadensis, E. cervinus, E. chrysopsidis, E. compositus, E. corymbosus, E. coulteri, E. decumbens, E. disparipilus, E. divergens, E. eatonii, E. elegantulus, E. filifolius, E. foliosus, E. glacialis, E. glaucus, E. howellii, E. inornatus, E. karvinskianus, E. klamathensis, E. latus, E. linearis, E. lonchophyllus, E. nivalis, E. oreganus, E. peregrinus, E. petrophilus, E. poliospermus, E. pumilus, E. simplex, E. speciosus, E. stanselliae, E. strigosus, E. tener, E. vagus
Synonyms Erigeron philadelphicus var. philadelphicus
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