Viburnum molle

Michx.

Softleaf Arrow-wood

G3Vulnerable Found in 2 roadless areas NatureServe Explorer →
G3VulnerableGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.149813
Element CodePDCPR070C0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderDipsacales
FamilyViburnaceae
GenusViburnum
Other Common Names
softleaf arrowwood (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 Date2024-02-07
Change Date2024-01-04
Edition Date2024-02-15
Edition AuthorsSE Ranking Workshop (2024)
Threat ImpactUnknown
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences21 - 80
Rank Reasons
Viburnum molle is a perennial shrub known from forested, rocky slopes in a scattered range through eight states in the midwestern and southeastern United States. There are at least 67 extant occurrences known, though long-term population declines are likely 30-50%. While rangewide threats are not fully documented, primary threats appear to be development, invasive species, recreation, and deer herbivory. There is concern about a lack of recruitment. Monitoring of populations should be conducted to improve our understanding of reproduction, plant abundance, threats, and trends, as well as continuing conservation measures to protect the species.
Range Extent Comments
Viburnum molle has a scattered, discontinuous range in the midwestern and southeastern United States from southwest Ohio, north central Indiana, west central Illinois, and southeast Iowa south to south central Tennessee and northwest Arkansas, including Kentucky and southern Missouri, and disjunct to southwest Iowa (Weakley and the Southeastern Flora Team 2023).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimen data, photo-based observation data, and NatureServe Network occurrence data documented between the years of 1993 and 2023, it is estimated that there are 67 extant occurrences known, excluding three occurrences that were failed to find and two occurrences considered historical (iNaturalist 2024, NatureServe 2023, SEINet 2024).
Threat Impact Comments
Viburnum molle is threatened by development, invasive species (including Lonicera japonica, L. mackii, Alliaria petiolata, Rosa multiflora, Eleagnus umbellata, Euonymous fortunei, and E. alata), recreation (especially off-road vehicles), and deer browse, though there is insufficient data, including anecdotal accounts, to understand rangewide scope and severity of threats for this species. Many occurrences in Kentucky note the absence of recruitment, which may be due to seed predation or small population size.
Ecology & Habitat

Habitat

Viburnum molle grows on "mesic bluffs, talus, and steep, forested slopes, usually over calcareous rock" (Weakley and the Southeastern Flora Team 2023). "Viburnum molle occurs in Arkansas on chert slopes at the base of north facing bluffs above creeks and rivers.... Habitats in Missouri which support Viburnum molle include north facing slopes, bluffs and limestone ledges along creeks and rivers..typically occur[ing] as understory elements receiving filtered or part day sunlight, at the mid-slope point, neither in the floodplain nor at the more xeric ridge crest" (Weckman 2002).
Terrestrial Habitats
Forest/WoodlandForest - HardwoodForest - MixedWoodland - HardwoodWoodland - Mixed
Other Nations (1)
United StatesN3
ProvinceRankNative
TennesseeS2Yes
IndianaS3Yes
IllinoisS2Yes
MissouriSUYes
ArkansasS1Yes
OhioS2Yes
OklahomaSNRYes
IowaS1Yes
KentuckyS2Yes
New YorkSNANo
Threat Assessments
ThreatScopeSeverityTiming
Unknown/undetermined

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (2)
Arkansas (1)
AreaForestAcres
Clifty CanyonOzark-St. Francis National Forest1,963
Missouri (1)
AreaForestAcres
Swan Creek Rare II Study AreaMark Twain National Forest7,310
References (7)
  1. Global Biodiversity Information Facility (GBIF). 2024. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2024).
  2. iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
  3. 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.
  4. NatureServe. 2023. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  5. Southwest Environmental Information Network (SEINet). 2024. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2024).
  6. Weakley, A.S., and Southeastern Flora Team. 2023. Flora of the southeastern United States. Edition of April 14, 2023. University of North Carolina Herbarium (NCU), North Carolina Botanical Garden, University of North Carolina, Chapel Hill. 2105 pp.
  7. Weckman, T. J. 2002. Reinstatement of Viburnum ozarkense (Caprifoliaceae): an endemic taxon of the interior highlands of Arkansas, Missouri, and Oklahoma. Sida 20(2): 849-860.