Home/Species/ Soft Aster

Symphyotrichum molle

(Rydb.) Nesom

Soft Aster

G3Vulnerable Found in 5 roadless areas NatureServe Explorer →

G3VulnerableGlobal Rank

Identity

Unique IDELEMENT_GLOBAL.2.130271

Element CodePDASTE80Z0

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicendemic to a single nation

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderAsterales

FamilyAsteraceae

GenusSymphyotrichum

Synonyms

Aster mollisRydb.

Concept Reference

Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.

Taxonomic Comments

Recognized at species level by Kartesz (1994 checklist, 1999). Jones (1984, Madrono 31:113-122) recognized and reinstated at the rank of species; formerly placed under synonomy with A. jessicae, a rare endemic of the Palouse Prairie of Washington and Idaho. In the past "Q" was added to GRANK because much of the existing herbarium material was identified as "Aster mollis?", "Aster cf mollis" or "Aster mollis X A". The situation appears to be the same in the field (Hollis Marriott, 1991). Although hybridization does occur, the species is distinctive enough to warrant recognition (Fertig 1993). Kartesz (1999) places it in the genus Symphyotrichum.

Conservation Status

Review Date1998-04-10

Change Date1998-04-10

Edition Date1993-12-23

Edition AuthorsFertig (rev. Fertig/Maybury 6/96)

Range Extent250-20,000 square km (about 100-8000 square miles)

Number of Occurrences21 - 80

Rank Reasons

A Wyoming endemic, known from about 30 occurrences, all but 1 of them in the Bighorn Mountains of the northcentral part of the state. Locally abundant at many sites. 13 of the populations show some evidence of hybridization or introgression with other Aster species.

Range Extent Comments

Soft aster is a Wyoming endemic restricted to the Bighorn Range (Big Horn, Johnson, Natrona, Sheridan, and Washakie counties) and Cliff Creek/Hoback Canyon area of Sublette County (Fertig et al. 1994). Jones (1984) also reports a specimen of Aster ascendens from Fremont County "with possible influence of A. mollis". Potential habitat may extend into Montana at the far northern end of the Bighorn Range (Crow Indian Reservation).

Occurrences Comments

Known from 30 occurrences, all but one of which is from the Bighorn Mountains. 13 occurrences show some evidence of hybridization or introgression with other Aster species.

Threat Impact Comments

Some occurrences may be threatened by grazing or trampling (Marriott 1992). Other evidence suggests that light grazing and fire may be stimulatory.

Ecology & Habitat

Habitat

Deep, calcareous soils on sagebrush grasslands, mountain meadows, limestone outcrops, and edges of aspen (Populus tremuloides) or pine woodlands. 1950-2600 m elevation.

Other Nations (1)

United StatesN3

Province	Rank	Native
Wyoming	S4	Yes
Montana	S2	Yes

Plant Characteristics

Economic Value (Genus)No

Roadless Areas (5)

Montana (2)

Area	Forest	Acres
Highlands	Beaverhead-Deerlodge National Forest	20,044
Silver King	Beaverhead-Deerlodge National Forest	64,289

Wyoming (3)

Area	Forest	Acres
Cloud Peak Contiguous	Bighorn National Forest	113,757
Devils Canyon	Bighorn National Forest	37,416
Walker Prairie	Bighorn National Forest	62,434

References (6)

Fertig, W. 1992. Distinguishing Aster mollis from "look-alike" species in the Bighorn Mountains. Wyoming Natural Diversity Database, Laramie. 5 pp.
Fertig, W., C. Refsdal, and J. Whipple. 1994. Wyoming rare plant field guide. Wyoming Rare Plant Technical Committee, Cheyenne. No pagination.
Flora of North America Editorial Committee (FNA). 2006b. Flora of North America north of Mexico. Vol. 20. Magnoliophyta: Asteridae, part 7: Asteraceae, part 2. Oxford Univ. Press, New York. xxii + 666 pp.
Jones, A. G. 1984. Typification of Aster jessicae Piper and reinstatement of A. mollis Rydberg (Asteraceae). Madroño 31:113-122.
Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
Marriott, H. J. 1992. Field survey for Aster mollis, Astragalus barrii and Lesquerella arenosa var. argillosa in northeast and central Wyoming. Unpublished report prepared for the Bureau of Land Management by the Wyoming Natural Diversity Database, Laramie, WY. 69 pp.