Plant Species: Trillium petiolatum, purple trillium
Kingdom: Plantae
Phylum: Magnoliophyta -- flowering plants
Class: Liliopsida -- monocotyledons
Order: Liliales
Family: Liliaceae -- lily
Genus: Trillium
Species: petiolatum
Common Name: purple trillium, purple wakerobin, round-leaved trillium, petioled wake-robin, Idaho trillium
Species Code: TRPE3
Origin: Native to moist places in thickets and forests and in moist meadows along streams in eastern Washington northeast Oregon and northern Idaho.
Rare: no
Form: forb, perennial, glabrous; rhizome thick, vertical, deep-seated, praemorse; stems mostly subterranean, 5-18 cm long.
Mature height: 2-6 inches
Duration: perennial
Longevity:
Habitat Type: forest, hawthorn thicket
Wetland Indicator Status: not listed
Leaves: 3, in a whorl subtending the flower, the petiole long and arising near ground level, broadly ovate to orbicular, base rounded to cordate at the base, tip rounded to obtuse, 8-13 cm long and wide, not mottled.
Flowers: solitary, sessile, borne near the ground and overtopped by the leaves; sepals 3, green, narrowly oblong-elliptic, 2.5-7 cm long; petals 3, flat, linear to lanceolate, usually purple, about as wide and slightly longer than the sepals: stamens 6.
Flower color: purple
Bloom: April, May
Bloom starts on: late April
Bloom ends on: mid May
Fruit: capsule, fleshy, semi-dehiscent; seeds many, ovoid, large.
Vegetation type:
Characteristics:
Reproduces sexually by seed.
Perennating organ is a thickened rhizome.
2n=10 (Hitchcock et al 1969, Flora of North America Editorial Committee 1993).
Diploids only are known.
Flowers are perfect.
Fruit is a fleshy, berry-like capsule.
Native peoples used the roots to make tea (Moerman 2003). The rhizomes, as well as the fruits and seeds, are reportedly poisonous (Flora of North America Editorial Committee 1993).
Rodents eat the seeds and rhizomes. Deer eat the flowers.
Comments: Trillium seeds are myrmecochorous. They have an elaiosome which is attractive to ants. Ants carry the elaiosome and attached seed back to their nest, where they remove or eat the elaiosome and discard the seed.
Sun requirement: full sun to partial shade
Soil moisture: moist
Precipitation:
Fire:
Hazards: may be poisonous
Sowing time: fall
Transplant time: fall
Stratification: cold moist
Seed yield: low
Seed harvest: difficult
Seed first harvest: no information available
Seed cleaning: no information available
Planting duration: no information available
Seed insect problem: no information available
Seed shatter: medium
Seed size: large
Seed harvest date: no information available
Seed comments:
Key words: native perennial upland forb
Alternate Genus:
Alternate Species:
Alternate Variety:
Propagation:
T. ovatum seeds should be collected and sown fresh for germination the following spring (Klest 2002).
The article does not give instructions for T. petiolatum, but it likely responds in the same manner.
Grows easily from seed (Hitchcock et al 1969).
Reproduces sexually by seed.
Notes: Trillium petiolatum hides its flower under the leaves. The flower is dark purple and not as showy or large as T. ovatum. Needs moist shade at least part of the day. More of a forest species but does sometimes grow under hawthorns. Common names include round-leaved trillium, purple trillium, petioled wake-robin (Skinner et al 2005).
References:
Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 7+ vols. New York and Oxford. Oxford University Press. Online at http://www.fna.org/FNA/
Hitchcock, C. Leo, Arthur Cronquist, Marion Ownbey, and J.W. Thompson. 1969. Vascular Plants of the Pacific Northwest. University of Washington Press. Seattle, WA. 5 vol.
Klest, Sheila M. 2002. Propagation Protocol for Western Trilliums. Native Plants Journal 3(1):22-23.
Moerman, Dan. 2003. Native American Ethnobotany: a Database of Foods, Drugs, Dyes and Fibers of Native American Peoples, Derived from Plants. University of Michigan-Dearborn. Online at http://herb.umd.umich.edu/ Accessed 1/3/07.
Skinner, David M., Paul Warnick, Bill French, and Mary Fauci. 2005. More Palouse Forbs for Landscaping. USDA NRCS Pullman Plant Materials Center and Palouse Prairie Foundation. Online at http://www.wsu.edu/pmc_nrcs/Docs/More_Forbs_for_Landscaping.pdf