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Marah oregana

(Torrey & A. Gray) Howell

Coast Manroot

G5Secure Found in 39 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.155360
Element CodePDCUC0J050
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderViolales
FamilyCucurbitaceae
GenusMarah
Synonyms
Echinocystis oregana(Torr. & A. Gray) Cogn.Marah oreganus(Torr. ex S. Wats.) T.J. HowellSicyos oreganusTorr. & A. Gray
Other Common Names
coastal manroot (EN) Coastal Manroot (EN) Marah d'Orégon (FR)
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 Date2025-03-26
Change Date1990-01-16
Edition Date2025-03-26
Edition AuthorsJohnson, J. (2025)
Threat ImpactUnknown
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Marah oregana is a vining herbceous plant found in forests, meadows, and disturbed areas in the Pacific Northwest from southern British Columbia to northern California. With a large range extent, more than 1000 occurrences, broad habitat preferences for abundant habitat, and tolerance for human disturbance, this species is considered secure.
Range Extent Comments
Marah oregana is found from British Columbia, Canada, to California, United States, mostly west of the Cascade-Sierra crest (FNA 2015). Range extent was estimated using herbarium specimens and photo-based observations documented between 1994 and 2025 (RARECAT 2024, GBIF 2025, iNaturalist 2025, SEINet 2025).
Occurrences Comments
By applying a 1 km separation distance to herbarium records and photo-based observations documented between 1994 and 2025, there are estimated to be more than 1000 occurrences rangewide (RARECAT 2024, GBIF 2025, iNaturalist 2025, SEINet 2025).
Threat Impact Comments
Although threats are not widely documented, Marah oreganus is potentially threatened by development, road maintenance, invasive species, and other threats in some places. However, their overall impact is likely negligible given the species' broad range, large number of occurrences, tolerance of light disturbance, and affinity for typically abundant habitats, as well as no obvious intrinsic vulnerabilities.
Ecology & Habitat

Habitat

Marah oregana grows in a wide variety of habitats including roadsides, disturbed areas, clearings, fields, dunes, Oregon white oak woodland, mixed conifer/broadleaf forest, exposed barren rocky summits, coastal shrublands, prairies, forest openings, coastal conifer forests, grassy headlands, and seacliffs (FNA 2015, Callahan 2022). Inland along the Columbia River and tributaries, it grows in riparian areas (Callahan 2022).
Terrestrial Habitats
Forest/WoodlandShrubland/chaparralGrassland/herbaceousOld fieldSand/duneCliffCropland/hedgerowSuburban/orchard
Palustrine Habitats
Riparian
Other Nations (2)
United StatesN5
ProvinceRankNative
OregonSNRYes
CaliforniaSNRYes
WashingtonSNRYes
IdahoSNRYes
WyomingSNRYes
CanadaN1
ProvinceRankNative
British ColumbiaS1Yes
Threat Assessments
ThreatScopeSeverityTiming
Unknown/undeterminedUnknownUnknownUnknown

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (39)
California (14)
AreaForestAcres
Black ButteMendocino National Forest15,461
ChinquapinShasta-Trinity National Forest22,040
Condrey Mtn.Klamath National Forest2,923
Cow CreekShasta-Trinity National Forest22,627
East ForkShasta-Trinity National Forest6,201
GrindstoneMendocino National Forest26,031
Little French CShasta-Trinity National Forest11,529
Murphy GladeShasta-Trinity National Forest1,015
Orleans Mtn. BSix Rivers National Forest17,183
PattisonShasta-Trinity National Forest29,299
Pilot CreekSix Rivers National Forest9,192
PortugueseKlamath National Forest18,915
South ForkShasta-Trinity National Forest16,786
UnderwoodSix Rivers National Forest6,591
Oregon (23)
AreaForestAcres
Bull Of The WoodsMt. Hood National Forest8,843
Calf - Copeland CreekUmpqua National Forest15,696
Cougar BluffUmpqua National Forest5,574
Drift CreekSiuslaw National Forest6,333
EagleMt. Hood National Forest16,841
FairviewUmpqua National Forest7,417
Hardesty MountainWillamette National Forest3,754
Hardesty MountainUmpqua National Forest2,597
Hebo 1aSiuslaw National Forest13,930
Jackson Creek AppendageUmpqua National Forest4,673
LarchMt. Hood National Forest12,961
LastUmpqua National Forest7,666
Limpy RockUmpqua National Forest6,782
Mclennon MountainWillamette National Forest8,085
Moose LakeWillamette National Forest5,013
Mt. HagenWillamette National Forest6,406
North KalmiopsisSiskiyou National Forests91,560
Roaring RiverMt. Hood National Forest27,316
Shasta CostaSiskiyou National Forests14,420
South KalmiopsisSiskiyou National Forests104,477
TenmileSiuslaw National Forest10,818
Williams CreekUmpqua National Forest5,844
WoahinkSiuslaw National Forest5,309
Washington (2)
AreaForestAcres
LightningOlympic National Forest7,179
Mt. Baker WestMt Baker-Snoqualmie National Forest25,390
References (8)
  1. Callahan, F. 2022. Marah Mysteries: Confusion over Wild Cucumber. Kalmiopsis, Vol. 24, P 8-17.
  2. Flora of North America Editorial Committee (FNA). 2015. Flora of North America north of Mexico. Vol. 6. Magnoliophyta: Cucurbitaceae to Droserceae. Oxford University Press, New York. 496 pp + xxiv.
  3. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  4. 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.
  5. Munz, P.A., with D.D. Keck. 1959. A California flora. Univ. California Press, Berkeley. 1681 pp.
  6. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  7. NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2024. Version: 1.1.1 (released Oct 01, 2024).
  8. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).