Pseudotrillium rivale

(S. Watson) S.B. Farmer

Brook Wakerobin

G3Vulnerable Found in 11 roadless areas NatureServe Explorer →
G3VulnerableGlobal Rank
VulnerableIUCN
High - lowThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.159369
Element CodePMLIL200T0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
IUCNVulnerable
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassMonocotyledoneae
OrderLiliales
FamilyLiliaceae
GenusPseudotrillium
Synonyms
Trillium rivaleS. Wats.
Other Common Names
brook wakerobin (EN) Klamath Wakerobin (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.
Taxonomic Comments
Trillium rivale was transferred to Pseudotrillium by Farmer and Schilling (2002), the same year Flora of North America vol. 26 was published. Pseudotrillium is accepted as the genus name for this taxon by the North American Trillium experts (Trillium workshop 2019).
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2019-10-23
Change Date2019-10-23
Edition Date2019-10-23
Edition AuthorsOliver, L. and K. Wayman
Threat ImpactHigh - low
Range Extent1000-5000 square km (about 400-2000 square miles)
Number of Occurrences21 - 80
Rank Reasons
Trillium rivale occurs in northern California and the southwestern corner of Oregon. The greatest threat to this species is wildfire.
Range Extent Comments
The extent of occurrence was calculated during the 2019 Trillium workshop. The species is known from the Klamath and Siskiyou Mountains in northwestern California, and north, through several southwestern counties in Oregon.
Occurrences Comments
If using herbarium specimens alone, there are on the order of 30 potential populations.
Threat Impact Comments
Wildfire is the greatest threat to this species, outside of its natural rarity. The Biscuit Fire data from 2002 indicate this fire covered the entire range of Psuedotrillium rivale. One fire event wouldn't destroy the species' populations because regrowth from roots would restore the populations, however, the habitat degradation from repeated fires would cause decline.
Ecology & Habitat

Reproduction

Trillium seeds have an elaiosome, an oily, lipid-rich attachment that is highly attractive to ants. The ants carry the seeds to their nest, eat the attachment, and leave the seeds in tunnels in their nests (FNA 2002a, Leege et al. 2010). The seeds later germinate en masse (Case and Case 1997). Yellow jackets (Vespula spp.) and other wasps are similarly attracted to the elaiosome. Yellow jackets are documented seed dispersers for three species (T. catesbaei, T. cuneatum, T. undulatum) (Zettler et al. 2001). Ants carry the seeds an average of about 1m whereas yellow jackets disperse seeds an average of 1.4m (Chafin 2010, Zettler et al. 2001). Long distance dispersers include mammals, such as white-tailed deer (Odocoileus virginianus) and woodchucks (Marmota monax) (Chafin 2010, Vellend et al. 2006). Similarly, it is suspected that elk (Cervus canadensis) and mule deer (Odocoileus hemionus) of the western U.S.A. are capable of dispersing seeds over long distances (Bartuszevige and Endress 2008).

All Trillium have rhizomes but the frequency of asexually reproduction varies (Chauhan et al. 2019, FNA 2002a, Ohara 1989).

Age to maturity, or flowering, is variable and has been recorded from 4 to 20 years depending on growing conditions (Case and Case 1997).
Terrestrial Habitats
Forest - Hardwood
Other Nations (1)
United StatesN3
ProvinceRankNative
OregonS3Yes
CaliforniaSNRYes
Threat Assessments
ThreatScopeSeverityTiming
5 - Biological resource usePervasive (71-100%)UnknownHigh (continuing)
5.3 - Logging & wood harvestingPervasive (71-100%)UnknownHigh (continuing)
7 - Natural system modificationsPervasive (71-100%)Serious - slightHigh (continuing)
7.1 - Fire & fire suppressionPervasive (71-100%)Serious - slightHigh (continuing)
7.1.1 - Increase in fire frequency/intensityPervasive (71-100%)Serious - slightHigh (continuing)

Plant Characteristics
DurationPERENNIAL, Long-lived
Economic Value (Genus)No
Roadless Areas (11)
California (9)
AreaForestAcres
Blue Creek Rare ISix Rivers National Forest12,134
KellySix Rivers National Forest5,195
Monkey CreekSix Rivers National Forest9,017
North Fork SmithSix Rivers National Forest37,898
PacksaddleSix Rivers National Forest3,862
Ship MountainSix Rivers National Forest11,936
SiskiyouKlamath National Forest54,039
Siskiyou BSix Rivers National Forest18,871
Slide CreekSix Rivers National Forest11,458
Oregon (2)
AreaForestAcres
North KalmiopsisSiskiyou National Forests91,560
South KalmiopsisSiskiyou National Forests104,477
References (17)
  1. Bartuszevige, A.M., and B.A. Endress. 2008. Do ungulates facilitate native and exotic plant spread? Seed dispersal by cattle, elk and deer in northeastern Oregon. Journal of Arid Environments 72: 904-913.
  2. Case, F.W. and R.B. Case. 1997. Trilliums. Timber Press, Portland Oregon.
  3. Chafin, L. G. 2010d. Species account for <i>Trillium persistens </i>for Georgia Department of Natural Resources. Online. Available: georgiawildlife.com/sites/default/files/uploads/wildlife/nongame/pdf/accounts/plants/trillium_persistens.pdf.
  4. Chauhan, H., A. Bisht, I. Bhatt, A. Bhatt, and D. Gallacher. 2019. <i>Trillium </i>- toward sustainable utilization of a biologically distinct genus valued for traditional medicine. The Botanical Review 85(3): 252-272.
  5. Farmer, S. B., and E. E. Schilling. 2002. Phylogenetic Analyses of Trilliaceae based on Morphological and Molecular Data. Systematic Botany 27(4): 674-692.
  6. Fernald, M.L., and A.C. Kinsey. 1943. Edible Wild Plants of Eastern North America. Idlewild Press, Cornwall-on-Hudson, NY. xiv+452 pp.
  7. Flora of North America Editorial Committee (FNA). 2002a. Flora of North America north of Mexico. Vol. 26. Magnoliophyta: Liliidae: Liliales and Orchidales. Oxford Univ. Press, New York. xxvi + 723 pp.
  8. 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.
  9. Klest, S.M. 2002. Propagation Protocol for Western Trilliums. Native Plants Journal 3(1):22-23.
  10. Leege, L. M., J. S. Thompson, D.J. Parris. 2010. The Responses of Rare and Common Trilliums (<i>Trillium reliquum</i>, <i>T. cuneatum</i>, and <i>T. maculatum</i>) to Deer Herbivory and Invasive Honeysuckle Removal. Castanea 75(4): 433-443.
  11. Lewis, Walter H., and Memory P.F. Elvin-Lewis. 1977. Medical Botany: Plants Affecting Man's Health. John Wiley and Sons, New York, New York. 515 p.
  12. Ohara, M. 1989. Life history evolution in the genus Trillium. Plant Species Biology 4:1-28.
  13. Rahman, S., M. Ismail, M. Khurram, I. Ullah, F. Rabbi, and M. Iriti. 2017. Bioactive steroids and saponins of the genus <i>Trillium. </i> Molecules 22(12): 2156.
  14. Trillium workshop group. 2019. , L. L. Gaddy, A. Floden, A. Frances, A. Highland, D. Leaman, T. Littlefield, C. Meredith, S. O'Bryan, L. Oliver, E. Schilling, A. Schotz, A. Walker, K. Wayman. Status assessment workshop at Mt. Cuba Center, Oct. 21-23, 2019.
  15. Vellend, M., J. Myers, S. Gardescu, and P. Marks. 2003. Dispersal of <i>Trillium</i> seeds by deer: Implications for long-distance migration of forest herbs. Ecology 84(4):1067-1072.
  16. Walck, J.L., J.M. Baskin, C.C. Baskin, and S.N. Hidayati. Defining transient and persistent seed banks in species with pronounced seasonal dormancy and germination patterns. Seed Science Research 15: 189-196. DOI: 10.1079/SSR2005209
  17. Zettler, J. A., T. P. Spira, and A. A. Craig. 2001. Yellow Jackets (<i>Vespula</i> spp.) Disperse <i>Trillium</i> (spp.) Seeds in Eastern North America. American Midland Naturalist 146(2):444-446.