Kingdom: Plantae

Phylum: Magnoliophyta -- flowering plants

Class: Magnoliopsida -- dicotyledons

Family: Ranunculaceae -- buttercup

Common Name: western meadow-rue

Species Code: THOC

Origin: Native to moist places in forests and meadows of western North America from Alaska to California east to Saskatchewan, Montana, Wyoming, and Colorado.

Rare: no

Form: forb, perennial from rhizomes and thin, fibrous roots; glabrous to glandular puberulent overall; stems erect, 40-100 cm tall, simple or branched, glabrous.

Mature height: 16-40 inches

Duration: perennial

Habitat Type: forest

Wetland Indicator Status: FACU

Leaves: mostly cauline, petiolate, alternate; blades 3-4 times ternate, the leaflets cuneate-obovate, 1.5-3 cm long, 3-lobed, glabrous to glandular.

Flowers: plants dioecious; flowers numerous, borne in an open terminal panicle with leaf-like bracts; apetalous; sepals usually 4, greenish-white to purple, ovate, 1.5-2 mm long in pistillate flowers, 3-4.5 mm long in staminate flowers; stamens 15-30, the filaments filiform, usually purplish, 4-8 mm long; ovaries glandular-puberulent, stigmas generally purplish, 3-4.5 mm long.

Flower color: green, sometimes purple tinged

Bloom: May, June, into July in montane elevations

Bloom starts on: early May

Bloom ends on: early June

Fruit: achene, spreading to recurved, fusiform, glandular, 5-9 mm long and 2-2.5 mm wide, slightly compressed, with 3 prominent veins on each side.

Characteristics:
Reproduces both sexually by seed and vegetatively by rhizomes.
x=7 (Flora of North America Editorial Committee 1993, University of British Columbia 2003).
2n=56 (University of British Columbia 2003).
Plants are dioecious.
The apetalous flowers and the dangling anthers suggest the plants are wind pollinated.
Fruit is an achene.
Polyploidy is present in the genus.
Native peoples used the plant medicinally.

Comments: T. occidentale is a variable species and several varieties have been proposed. St. John (1963) recognized var. palousense for the plants of Kamiak Butte and the Blue Mountains. Hitchcock et al (1969) did not recognize any varieties. Most newer floras follow suit and place var. palousense in synonymy with the species.

Sun requirement: high shade tolerance

Soil moisture: mesic

Fire: Easily killed by fire but may survive cool fires which do not consume the duff layer and kill the rhizomes (Crane & Fischer 1986).

Sowing time: fall

Transplant time: spring

Pretreatment: gibberellic acid presoak followed by cold moist stratification

Seed yield: low

Seed harvest: easy

Seed first harvest: no information available

Seed cleaning: no information available

Planting duration: no information available

Seed insect problem: no information available

Seed shatter: no information available

Seed size: medium

Seed harvest date: no information available

Herbaria: Specimen data and digital resources from The Consortium of Pacific Northwest Herbaria

Key words: native upland perennial forest forb

Propagation:
Reproduces both sexually by seed and vegetatively by rhizomes.
2 protocols in the Native Plant Network
Glacier National Park, Montana
University of Kentucky

Notes: Makes a good shade plant in the landscape, not too aggressive, leaves are interesting (Idaho Native Plant Society 1999).

References:
Crane, M.F., and William C. Fischer. 1986. Fire Ecology of the Forest Habitat Types of Central Idaho. UDSA Forest Service Intermountain Research Station General Technical Report INT-218.

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.

Idaho Native Plant Society. 1999. Native Plants of Northern Idaho for Landscaping and Restoration. INPS White Pine Chapter. Moscow, ID. Online at http://www.idahonativeplants.org/guides/NorthIdahoGuide.aspx

St. John, Harold. 1963. Flora of Southeastern Washington and of Adjacent Idaho. 3rd edition. Outdoor Pictures. Escondido, CA.

University of British Columbia. 2003. British Columbia Flora. University of British Columbia Botanical Garden and Centre for Plant Research. Accessed 9/1/09 online at http://www.bcflora.org/

Links:
Plant Profile from the USDA PLANTS Database
Species description from Flora of North America
Species information from the University of Washington Herbarium