Roadless Areas
Home/Species/ Mountain Whitlow-grass

Draba sphaeroides

Payson

Mountain Whitlow-grass

G2Imperiled (G2G3) Found in 2 roadless areas NatureServe Explorer →
G2ImperiledGlobal Rank
High - lowThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.140775
Element CodePDBRA112F0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderCapparales
FamilyBrassicaceae
GenusDraba
Other Common Names
Ball Draba (EN) ball draba (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 Date2024-10-18
Change Date1999-01-21
Edition Date2024-10-18
Edition AuthorsJan Nachlinger (1997), rev. A. Tomaino (2009), rev. Johnson, J. (2024)
Threat ImpactHigh - low
Range Extent1000-5000 square km (about 400-2000 square miles)
Number of Occurrences6 - 20
Rank Reasons
Draba sphaeroides is a perennial herb known from only three mountain ranges in Elko County, Nevada. It occurs in alpine and subalpine habitats with uncertain threat levels.
Range Extent Comments
Draba sphaeroides is endemic to Elko County, Nevada in the Jarbridge and Ruby Mountains, and East Humboldt Range (Holmgren et al. 2005). Draba sphaeroides is occasionally listed as native to Steens Mountain in Oregon but the plants there belong to Draba cusickii var. cusickii (Mansfield 1999). Specimens from the Snake Range in White Pine County, Nevada, are likely misidentified Draba pedicellata plants. Range extent was estimated to be 2,900 sq km using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1993 and 2024 (iNaturalist 2024, SEINet 2024, CPNWH 2024, NatureServe 2024).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1993 and 2024, it is estimated that there 12 occurrences rangewide (iNaturalist 2024, SEINet 2024, CPNWH 2024, NatureServe 2024).
Threat Impact Comments
Introduced Mountain Goats in the Ruby Mountains can easily access the remote, rocky habitat of Draba sphaeroides but it is unknown whether these animals consume the Draba plants. Most occurrences of D. sphaeroides are known from areas near hiking trails and access roads but this is likely due to sampling bias. Many areas of potential habitat are remote and difficult to access and threats are likely low.
Ecology & Habitat

Habitat

Draba sphaeroides grows on rock outcrops, talus, and soil pockets on rocky slopes, in the alpine zone and subalpine whitebark pine (Pinus albicaulis), limber pine (Pinus flexilis), or mountain mahogany (Cercocarpus ledifolius) communities (FNA 2010, SEINet 2024).
Terrestrial Habitats
Woodland - ConiferWoodland - MixedBare rock/talus/screeCliff
Other Nations (1)
United StatesN2
ProvinceRankNative
NevadaS2Yes
Threat Assessments
ThreatScopeSeverityTiming
6 - Human intrusions & disturbanceRestricted (11-30%)Moderate - slightHigh (continuing)
6.1 - Recreational activitiesRestricted (11-30%)Moderate - slightHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesLarge (31-70%)Serious - slightHigh (continuing)
8.1 - Invasive non-native/alien species/diseasesLarge (31-70%)Serious - slightHigh (continuing)
8.1.2 - Named speciesLarge (31-70%)Serious - slightHigh (continuing)

—

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (2)
Nevada (2)
AreaForestAcres
Ruby - Lamoille CynHumboldt-Toiyabe National Forest32,771
Ruby - MarshHumboldt-Toiyabe National Forest10,164
References (11)
  1. 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).
  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. Holmgren, N. H. 2004. A new variety of <i>Draba pedicellata</i> and a lectotype for <i>D. cusickii</i> (Brassicaceae). Brittonia 56:107-114.
  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. iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
  6. Kartesz, J.T. 1988. A flora of Nevada. Ph.D. dissertation. Univ. of Nevada, Reno. 3 volumes. 1729 pp.
  7. 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.
  8. Mansfield, D.H. 1999. Flora of Steens Mountain. Oregon State University Press, Corvallis. 410 pp.
  9. NatureServe. 2024. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  10. 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.
  11. Southwest Environmental Information Network (SEINet). 2024. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2024).