Draba ramulosa

Rollins

Tushar Mountain Draba

G1Critically Imperiled Found in 2 roadless areas NatureServe Explorer →
G1Critically ImperiledGlobal Rank
HighThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.142063
Element CodePDBRA112X0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderCapparales
FamilyBrassicaceae
GenusDraba
Other Common Names
Tushar Mountain Whitlow-grass (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.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-04-23
Change Date1995-08-04
Edition Date2025-04-23
Edition AuthorsR. Douglas Stone, rev. B. Franklin (1996), rev. A. Tomaino (2009), rev. L. Oliver (2011), rev. M. McCormick (2023) and N. Ventrella (2025)
Threat ImpactHigh
Range Extent<100 square km (less than about 40 square miles)
Number of Occurrences1 - 5
Rank Reasons
Draba ramulosa is a perennial forb occurring on Tertiary ash-flow tuffs in alpine communities on talus and scree slopes of the Tushar Mountains of Utah in the western United States. This is an endemic plant of one known occurrence with an extremely narrow range. It is primarily threatened by climate change and herbivory impacts from introduced mountain goats. Trends from permanent monitoring plots established for Draba ramulosa show declines in plant density from 2018 to 2022, indicating that conservation actions are urgently needed.
Range Extent Comments
Draba ramulosa occurs in the western United States, where it is endemic to the Tushar Mountains of Beaver and Piute counties, Utah (Welsh et al. 2015). Range extent was calculated using data from the Utah Rare Plant Database (2023), excluding historical observations over 40 years old (UNHP 2023).
Occurrences Comments
By applying a 2 km separation distance to population location data from the Utah Rare Plant Database (2023), there is only one known occurrence of this species (UNHP 2023).
Threat Impact Comments
Threats to Draba ramulosa include grazing-related impacts, climate change, and drought (UNHP 2023, UNPS 2025). Recreational use of habitat, such as foot traffic, biking, dispersed camping, winter recreation, and off-road vehicles may pose a threat to some populations (Franklin 2005, Allphin 2023).

Mountain goats were introduced to the Tushar Mountains in 1986 for the purpose of trophy hunting and are now naturalized to the region (Taye 1995). This species is threatened by grazing by mountain goats (UNHP 2023, UNPS 2025). In an ungulate forage utilization study of high alpine plants of the Tushars, Draba ramulosa was present within three mountain goat feeding sites, three deer feeding sites, and three random sampling points, but no utilization of this species was recorded (Shipp 2022). However, when a fecal DNA analysis was conducted on mountain goats in the Tushars, 8.2% of samples had Draba ramulosa DNA, indicating that this species is utilized by mountain goats (Allphin 2025). In contrast, no DNA of this species was found in deer fecal samples. Populations of Draba ramulosa are in decline, and the Utah Natural Heritage Program considers mountain goats to have a serious impact to this species (UNHP 2023).

Climate change is also a threat likely impacting this species throughout its range (Wrobleski 2023). Droughts and rapid snowmelt due to wind-blown sediments are melting snowpack earlier than normal in the region (UNPS 2025), and as of 2025, according to the North American Drought Monitor, Utah is in "severe" to "exceptional" drought in many parts of the state, which is likely impacting this species in similar ways as it is other perennial forbs in Utah (Hadwen et al. 2025).
Ecology & Habitat

Diagnostic Characteristics

Resembles D. ventosa in its production of numerous creeping rootstocks and elongated cluster of gray leaves. However, D. ramulosa differs by having leaves on its fertile stems while D. ventosa is scapose, and its siliques are elliptical rather than oval, broadly ovate, or orbicular as in D. ventosa. The trichomes of D. ramulosa are also finer and more highly branched than those of D. ventosa.

Habitat

Draba ramulosa occurs on loose, gravelly talus slopes and rock outcrops above timberline from 3300-3600 m in elevation (FNA 2010). This plant is found on thermally-modified Teritary ash-flow tuffs in the Marysvale Volcanic centrum (Welsh et al 2015).

Reproduction

Draba ramulosa produces flowers in June-July (Utah Native Plant Society 2025).
Terrestrial Habitats
AlpineBare rock/talus/scree
Other Nations (1)
United StatesN1
ProvinceRankNative
UtahS1Yes
Threat Assessments
ThreatScopeSeverityTiming
6 - Human intrusions & disturbanceUnknownUnknownUnknown
6.1 - Recreational activitiesUnknownUnknownUnknown
8 - Invasive & other problematic species, genes & diseasesPervasive (71-100%)Serious or 31-70% pop. declineHigh (continuing)
8.1 - Invasive non-native/alien species/diseasesPervasive (71-100%)Serious or 31-70% pop. declineHigh (continuing)
8.1.2 - Named speciesPervasive (71-100%)Serious or 31-70% pop. declineHigh (continuing)
11 - Climate change & severe weatherPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)
11.2 - DroughtsPervasive (71-100%)Moderate or 11-30% pop. declineHigh (continuing)

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (2)
Utah (2)
AreaForestAcres
Bullion - DelanoFishlake National Forest14,917
Tushar MountainFishlake National Forest39,992
References (13)
  1. Allphin, L. 2023. Update on monitoring of populations from five, rare, high elevation endemics in the Tushar Mountains, Fishlake National Forest, Utah. Presentation at the 2023 Rare Plant Meeting, Utah Native Plant Society. Online. Available: <a href="https://www.youtube.com/watch?v=w1rodn8JOe0&amp;list=PLLv26qEbGIKERG4fUZeB1Rfygq9FK0VsY&amp;index=5">www.youtube.com/watch?v=w1rodn8JOe0&list=PLLv26qEbGIKERG4fUZeB1Rfygq9FK0VsY&index=5</a> (accessed 2025).
  2. Flora of North America Editorial Committee (FNA). 2010. Flora of North America north of Mexico. Vol. 7. Magnoliophyta: Salicaceae to Brassicaceae. Oxford University Press, New York. xxii + 797 pp.
  3. Franklin, M.A. 2005. Plant information compiled by the Utah Natural Heritage Program: A progress report. Publication Number 05-40. Utah Division of Wildlife Resources, Salt Lake City, Utah. 341 pp. [http://dwrcdc.nr.utah.gov/ucdc/ViewReports/plantrpt.htm]
  4. Holmgren, N.H., P.K. Holmgren, and A. Cronquist. 2005. Intermountain flora. Volume 2, part B. Subclass Dilleniidae. The New York Botanical Garden Press. 488 pages.
  5. 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.
  6. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  7. Rollins, R.C. 1993a. The Cruciferae of continental North America: Systematics of the mustard family from the Arctic to Panama. Stanford Univ. Press, Stanford, California. 976 pp.
  8. Shipp, Heather. 2022. Monitoring of foraging sites for ungulates within alpine plant communities and establishment of long-term monitoring plots for rare <i>Castilleja parvula</i> var. <i>parvula</i> in the Tushar Mountains, Utah. M.S. Thesis. Brigham Young University, Provo, UT. 126 pp.
  9. Taye, A. C. 1995. Alpine vascular flora of the Tushar Mountains, Utah. Great Basin Naturalist 55(3): 225-236.
  10. Utah Native Plant Society. 2003-2025. Utah rare plant guide. Utah Native Plant Society, Salt Lake City, UT. Online. Available: https://www.utahrareplants.org. (accessed 2025).
  11. Utah Native Plant Society (UNPS). 2025. 2016-2025 UNPS Utah Rare Plant Master List . Online. Available: www.utahrareplants.org/rpg_species.html (Accessed 2025).
  12. Utah Natural Heritage Program (UNHP). 2023. Element Subnational Ranking Form: <i>Draba ramulosa</i> in Biotics 5 database. NatureServe, Arlington, Virginia (accessed 9 April 2025).
  13. Welsh, S.L., N.D. Atwood, S. Goodrich, and L.C. Higgins. (Eds). 2015. A Utah flora, fifth edition, revised 2015. Monte L. Bean Life Science Museum, Provo, Utah. 987 pp.