Nutt. ex Torr. & Gray
Identity
Unique IDELEMENT_GLOBAL.2.140411
Element CodePDLOA03090
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderViolales
FamilyLoasaceae
GenusMentzelia
Other Common Namesunited blazingstar (EN)
Concept ReferenceKartesz, 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 Date2024-07-09
Change Date2024-07-09
Edition Date2024-07-09
Edition AuthorsN. Ventrella (2024)
Threat ImpactUnknown
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences81 to >300
Rank ReasonsMentzelia congesta is an annual herb occurring on disturbed slopes, pinyon/juniper woodlands, pine forests, and sagebrush scrub in western North America in Idaho, Oregon, California, and Nevada in the United States. It is known from (likely more than) 150 occurrences that are potentially threatened by development, rights-of-way maintenance, invasive species, climate change and drought. However, these threats are considered negligible given the broad range and medium to large number of occurrences for this species.
Range Extent CommentsMentzelia congesta occurs in western North America in Idaho, Oregon, California, and Nevada in the United States (FNA 2016). Range extent was estimated to be 421,000 square kilometers using herbarium specimens and photo-based observations documented between 1993 and 2024 (GBIF 2024, iNaturalist 2024, SEINet 2024).
Occurrences CommentsBy applying a 1 km separation distance to herbarium specimens and photo-based observations documented between 1993 and 2024, it is estimated that there are approximately 150 occurrences rangewide (GBIF 2024, iNaturalist 2024, SEINet 2024). However, this desert annual may be underrepresented in collections due to its small stature and highly variable population numbers that are dependent on annual precipitation.
Threat Impact CommentsAlthough threats are not widely documented, Mentzelia congesta is potentially threatened by development, rights-of-way maintenance, invasive species, climate change and drought, and other threats in some places. However, their overall impact is likely negligible given the species' broad range, tolerance of light disturbance, and affinity for typically abundant habitats, as well as no obvious intrinsic vulnerabilities.