Muhl.
Identity
Unique IDELEMENT_GLOBAL.2.128125
Element CodePDULM04090
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
IUCNLeast concern
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderUrticales
FamilyUlmaceae
GenusUlmus
SynonymsUlmus fulvaMichx.
Other Common NamesOrme rouge (FR) Red Elm (EN) slippery elm (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 Date2024-07-10
Change Date2024-07-10
Edition Date2024-07-10
Edition AuthorsN. Ventrella (2024)
Threat ImpactHigh
Range Extent>2,500,000 square km (greater than 1,000,000 square miles)
Number of Occurrences> 300
Rank ReasonsUlmus rubra was once a widespread tree of eastern North American forests, occurring on lower slopes, alluvial flood plains, riverbanks, and bottom lands from Ontario and Quebec, Canada and North Dakota, United States south to Florida and west to Texas. Since the 1930s and 1940s, the introduction of the exotic fungus, Dutch elm disease, has impacted millions of trees and led to range-wide declines. Dutch elm disease primarily affects mature individuals, and the impact of Dutch elm disease to U. rubra populations is site-specific, with high elm sapling regeneration occurring at some sites, and conversion to competing woody species occurring at others. The Conservation Status of this species should be reviewed frequently to detect changes in the impact of the pest.
Range Extent CommentsUlmus rubra occurs in eastern and central North America from Ontario and Quebec, Canada and North Dakota in the United States south to Florida west to Texas (FNA 1997). Range extent was estimated to be over 3 million 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 well over 300 occurrences rangewide (GBIF 2024, iNaturalist 2024, SEINet 2024). However, this taxon is commonly cultivated, and iNaturalist observations (>11,000) were not evaluated for evidence of cultivation (iNaturalist 2024).
Threat Impact CommentsThe most significant threat to Ulmus rubra is from Dutch elm disease, an introduced fungal pathogen which has killed an estimated hundreds of millions of trees since the 1930s (Brunet et al. 2016). Dutch elm targets large, mature trees, and often spares small-diameter saplings (Marks 2017). The impact of this disease to forest structure is site dependent, with elm saplings returning to some sites after mature elms are killed or reverting to competing (non-elm) tree species at other sites. This species also hybridizes with the introduced Siberian elm (U. pumila) where their ranges overlap (FNA 1997).