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Rydberg's fleabane

hyssop-leaf fleabane, vergerette à feuilles d'hysope

Habit Perennials, 2.5–6 cm; taprooted, caudex branches relatively short, thick. Perennials, 5–35 cm; rhizomatous, fibrous-rooted, caudices sometimes branched.
Stems

erect, finely hirsutulous to villosulous, eglandular.

erect, sparsely and loosely strigose to strigoso-villous, eglandular.

Leaves

mostly basal (persistent);

blades linear-oblanceolate to narrowly spatulate, 10–50 × 1–3 mm, cauline mostly on proximal 1/2 of stems, reduced distally, margins entire (apices obtuse to rounded), abaxial faces glabrous, adaxial glabrous or sparsely villous, eglandular.

basal and proximal cauline much reduced or present as scales;

cauline blades linear to linear-oblong or oblong-lanceolate, 10–30 × 1–5 mm, largest at midstem, then relatively even-sized to peduncles, margins entire, sometimes prominently ciliate, faces glabrous or sparsely villous.

Involucres

5–6 × 7–12 mm.

4–6 × 6–12 mm.

Ray florets

15–35;

corollas usually bluish to purplish, rarely white, 6–9 mm, laminae coiling.

20–50;

corollas white, less commonly pinkish, or aging pinkish, 4–8 mm, laminae not coiling or reflexing.

Disc corollas

3.7–5 mm.

3–4.6 mm.

Phyllaries

in 2–3 series, densely and finely hirsuto-villous (hairs without colored cross walls), minutely and inconspicuously glandular.

in 2–3 series, loosely and sparsely strigose, eglandular.

Heads

1.

1(–5).

Cypselae

1.8–2 mm, 2-nerved, faces sparsely strigose;

pappi: outer of setae, inner of 15–20 bristles.

1.3–1.6 mm, 5–6-nerved, faces glabrous;

pappi: outer of setae, inner of 25–35 bristles.

2n

= 18.

Erigeron rydbergii

Erigeron hyssopifolius

Phenology Flowering Jun–Aug. Flowering Jun–Aug.
Habitat Open subalpine to alpine slopes Open woods, river gravel, rock ledges and crevices, gravel barrens, roadsides
Elevation 2000–3200 m (6600–10500 ft) 0–500 m (0–1600 ft)
Distribution
from FNA
ID; MT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
ME; MI; NH; NY; VT; AB; MB; NB; NF; NS; NT; NU; ON; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
Discussion

Variety villicaulis, from Anticosti Island (Quebec) and Newfoundland, has been distinguished on the basis of its relatively shorter stature (mostly 3–15 cm) and greater ratio of peduncle to leafy-stem lengths (stems and peduncles as long as or longer than the leafy parts of stems); the distinction appears to be arbitrary.

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

Source FNA vol. 20, p. 293. FNA vol. 20, p. 277.
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. 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. 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 E. hyssopifolius var. anticostensis, E. hyssopifolius var. villicaulis
Name authority Cronquist: Brittonia 6: 191. (1947) Michaux: Fl. Bor.-Amer. 2: 123. (1803)
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