Home/Species/ Howell's Fleabane

Erigeron howellii

Gray

Howell's Fleabane

G2Imperiled Found in 2 roadless areas NatureServe Explorer →

G2ImperiledGlobal Rank

HighThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.130050

Element CodePDAST3M1U0

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicendemic to a single nation

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderAsterales

FamilyAsteraceae

GenusErigeron

Other Common Names

Howell's fleabane (EN)

Concept Reference

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

Taxonomic Comments

Cronquist (1955) commented that Erigeron howellii is "very closely related to the widespread and variable E. peregrinus, but the weak morphological characters are bolstered by the restricted distribution and specialized lowland habitat." Generally considered distinct by later authors (Kartesz 1994, 1999; Flora of North America 2006).

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2024-08-26

Change Date1991-02-08

Edition Date2024-08-26

Edition AuthorsGamon, J. & K. Maybury, rev. A. Olivero (2003), rev. K. Gravuer (2008), rev. Johnson, J. (2024)

Threat ImpactHigh

Range Extent250-1000 square km (about 100-400 square miles)

Number of Occurrences6 - 20

Rank Reasons

Erigeron howellii is endemic to the central portion of the Columbia River Gorge in Washington and Oregon, with eleven occurrences believed extant. Many occurrences are small, with less than 500 plants. Nevertheless, some occurrences inhabit cliff faces where they are relatively inaccessible, and many occur within managed areas where they are protected from development. Some occurrences may be threatened by timber harvesting, road construction, herbicide application, fire, climate change, and recreational use.

Range Extent Comments

Erigeron howellii is endemic to the central portion of the Columbia River Gorge in Washington and Oregon. It is known from Skamania County, Washington and Clackamas, Hood River, and Multnomah Counties, Oregon (WAHP 2003, OBIC 2024). Range extent was estimated using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1993 and 2024 (GBIF 2024, iNaturalist 2024, NatureServe 2024,CPNWH 2024).

Occurrences Comments

Eleven occurrences have been documented as extant since 1993, with an additional nine occurrences not documented in the past 30 years and four occurrences considered historical (NatureServe 2024).

Threat Impact Comments

Some populations may be subject to various potentially detrimental land management activities, including timber harvesting, road construction, and herbicide application (WAHP 2003). Recreational use is an increasing threat as the Columbia River Gorge National Scenic Area becomes more popular (WAHP 2003). Indiscriminate collection could be a potential problem (Meinke 1982). Any impact reducing the required moisture level of the habitat, including regional or local changes, could also be an issue (Meinke 1982). Large fires are becoming more frequent in the Pacific Northwest, and several occurrences of Erigeron howellii were impacted by the 48,000 acre Eagle Creek fire in 2017. Areas affected by fire are also at increased risk for erosion and debris flows (USFS 2024). The impacts of these fires on populations of Erigeron howellii are unknown at this time.

Ecology & Habitat

Description

Often found in clusters of plants with several stems rising from a rhizome. Perennial, 20-50 cm tall. stems mostly hairless but a little hairy under the flower heads. Leaves thin, smooth,and shiny green, lower leaves with egg-shaped blades abruptly contracted to a petiole, upper leaves strongly clasp the stem at their bases. There is one flower head per stem which has loose, glandular involucral bracts. Flower heads include a yellow central disk 12-20 mm wide, comprised of disc florets with distinctly flared corollas 4-5 mm long. The central disk is surrounded by 30-50 white ray florets, each 13-25 mm long and 2-4 mm wide. Fruit is an achene with 5 asymmetrical nerves and a pappus of 20-30 bristles (Meinke 1982, WA HP 2003, Oregon Flora Project 2007).

Diagnostic Characteristics

Could potentially be confused with E. peregrinus and E. aliceae. Distinguished from E. peregrinus by its longer (4-5 mm) and more flaring disc corollas; by its ray flowers usually white (rays of E. peregrinus are ofter pink to purple); by its lower leaves contracting abruptly to the petiole (as opposed to tapering to the petiole in E. peregrinus) and by its thin and strongly clasping stem leaves. Distinguished from E. aliceae by its smooth, less elongate leaves (Meinke 1982, WA HP 2003, Oregon Flora Project 2007).

Habitat

Erigeron howelliiis restricted to the Columbia River Gorge primarily on steep, north-facing, protected slopes. They grow in moist (e.g. from seepage), often rocky places, generally in microsites that have very little soil development and limited development of competing vegetation; the sites are essentially stable, herb-dominated communities within Douglas fir forest (FNA 2006, OBIC 2024).

Terrestrial Habitats

Forest/WoodlandForest - ConiferBare rock/talus/screeCliff

Other Nations (1)

United StatesN2

Province	Rank	Native
Oregon	S2	Yes
Washington	S2	Yes

Threat Assessments

Threat	Scope	Severity	Timing
4 - Transportation & service corridors	Restricted (11-30%)	Moderate or 11-30% pop. decline	Moderate (short-term)
4.1 - Roads & railroads	Restricted (11-30%)	Moderate or 11-30% pop. decline	Moderate (short-term)
5 - Biological resource use	Large (31-70%)	Moderate or 11-30% pop. decline	High (continuing)
5.2 - Gathering terrestrial plants	Large (31-70%)	Slight or 1-10% pop. decline	High (continuing)
5.2.1 - Intentional use (species being assessed is the target)	Large (31-70%)	Slight or 1-10% pop. decline	High (continuing)
5.3 - Logging & wood harvesting	Restricted (11-30%)	Moderate - slight	Moderate (short-term)
5.3.4 - Unintentional effects: large scale (species being assessed is not the target) [harvest]	Restricted (11-30%)	Moderate - slight	Moderate (short-term)
6 - Human intrusions & disturbance	Large (31-70%)	Slight or 1-10% pop. decline	High (continuing)
6.1 - Recreational activities	Large (31-70%)	Slight or 1-10% pop. decline	High (continuing)
7 - Natural system modifications	Restricted (11-30%)	Serious - moderate	Moderate (short-term)
7.1 - Fire & fire suppression	Restricted (11-30%)	Serious - moderate	Moderate (short-term)
7.1.1 - Increase in fire frequency/intensity	Restricted (11-30%)	Serious - moderate	Moderate (short-term)
9 - Pollution	Small (1-10%)	Serious or 31-70% pop. decline	High (continuing)
9.3 - Agricultural & forestry effluents	Small (1-10%)	Serious or 31-70% pop. decline	High (continuing)
9.3.3 - Herbicides and pesticides	Small (1-10%)	Serious or 31-70% pop. decline	High (continuing)
11 - Climate change & severe weather	Pervasive (71-100%)	Moderate or 11-30% pop. decline	Moderate (short-term)
11.1 - Habitat shifting & alteration	Pervasive (71-100%)	Moderate or 11-30% pop. decline	Moderate (short-term)

Plant Characteristics

DurationPERENNIAL

Economic Value (Genus)No

Roadless Areas (2)

Oregon (2)

Area	Forest	Acres
Eagle	Mt. Hood National Forest	16,841
Larch	Mt. Hood National Forest	12,961

References (15)

Consortium of Pacific Northwest Herbaria (CPNWH). 2024. Online database of vascular plant specimens from the Pacific Northwest. Online. Available: http://www.pnwherbaria.org/index.php (accessed 2024).
Cronquist, A. 1955. Compositae. In C.L. Hitchcock, A. Cronquist, M. Ownbey, and J.W. Thompson (eds.). Vascular plants of the Pacific Northwest. Part 5. Univ. Washington Press, Seattle. 343 pp.
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.
Franklin, J.F., and C.T. Dyrness. 1973. Natural vegetation of Oregon and Washington. U.S. Forest Service, General Technical Report PNW-8. Portland, OR.
Global Biodiversity Information Facility (GBIF). 2024. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2024).
iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
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.
Meinke, R.J. 1982. Threatened and Endangered Vascular Plants of Oregon: An Illustrated Guide. U.S. Fish and Wildlife Service, Region 1, Portland, Oregon. 326 pp.
NatureServe. 2024. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
Oregon Biodiversity Information Center (OBIC). 2024. Biodiversity Tracking and Conservation System (Biotics 5). Oregon Biodiversity Information Center, Institute for Natural Resources, Portland State University, Portland, Oregon.
Oregon Flora Project. 2007 last update. Rare Plant Guide. Online. Available: http://www.oregonflora.org/rareplants/index.php (Accessed 2008).
US Forest Service (USFS). 2024. Eagle Creek Fire Story & Data. https://www.fs.usda.gov/detailfull/crgnsa/fire/?cid=fseprd567631
Washington Natural Heritage Program. 1994. Endangered, threatened and sensitive vascular plants of Washington. Dept. of Natural Resources, Olympia, Washington. 52 pp.
Washington Natural Heritage Program and USDI Bureau of Land Management (BLM). 2003. Field guide to selected rare plants of Washington. Online. Available: http://www.dnr.wa.gov/nhp/refdesk/fguide/htm/fsfgabc.htm. Accessed 2003, May 9.

Erigeron howellii

Description

Diagnostic Characteristics

Habitat

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