Palouse Prairie Foundation plant database (under development)
Genus species:      Common name:     Match: Full Partial
Plant Species: Perideridia gairdneri, Gairdner’s yampah.


Kingdom: Plantae
Phylum: Magnoliophyta -- flowering plants
Class: Magnoliopsida -- dicotyledons
Family: Apiaceae
Genus: Perideridia
Species: gairdneri
Subspecies: The Palouse phase is ssp. borealis.
Common Name: Gairdner’s yampah
Species Code: PEGA3
Origin: Native to vernally moist grasslands, meadows, and open forest of western North America from southern British Columbia to California and east to Colorado and Montana.
Rare: no


Form: forb, perennial from a tuberous-thickened, solitary and sometimes fascicled root; stem solitary, sometimes branched above, 40-120 cm tall, glabrous.
Duration: perennial
Longevity: moderate
Habitat Type: prairie, shrub thickets, forest, wetland
Wetland Indicator Status: FAC


Leaves: several, well distributed along the stem, once or twice pinnate or ternate with elongate segments, slightly reduced upward.
Mature height: 16-40 inches
Flowers: borne in terminal and lateral compound umbels, 2.5-7 cm wide in flower; rays to 6 cm long; corolla white, anthers exserted.
Flower color: white
Bloom: July, August
Bloom starts on: July 23
Bloom ends on: August 21
Fruit: schizocarp, suborbicular, 2-3 mm long and wide, glabrous, somewhat flattened with prominent ribs.
Vegetation type:
Characteristics:
Carum gairdneri in St. John 1963, Piper & Beattie 1914.
Reproduces sexually by seed.
400,000 seeds/lb (USDA NRCS PLANTS Database 2009).
Perennating organ is a tuber-like thickened portion of the root.
For ssp. borealis 2n=40, 80, 120 (Baldwin et al 2004).
Plants are andromonoecious, having both perfect and staminate flowers.
Perfect flowers are protandrous (Schlessman & Barrie 2004).
Polyploidy is present.
Roots are edible raw, cooked or dried and were widely used by Native Americans.
Fruit is a schizocarp separating into 2 mericarps.
Roots are eaten by bears and rodents (Craighead et al 1963).
Comments:


Sun requirement: full sun to partial shade
Soil moisture: mesic
Precipitation: 14-24 inches (USDA NRCS PLANTS Database 2009).
Fire:
Hazards:


Sowing time: fall
Transplant time: fall
Stratification: cold moist
Seed yield: medium
Seed harvest: early September to mid October
Seed first harvest: 3rd season
Seed cleaning: easy
Planting duration: long
Seed insect problem: none noted
Seed shatter: low
Seed size: medium
Seed harvest date: early September to mid October
Seed comments:


Herbaria: Specimen data and digital resources from The Consortium of Pacific Northwest Herbaria
Key words:
Alternate Genus: Carum
Alternate Species:
Alternate Variety:


Propagation:
3 protocols in the Native Plant Network
Glacier National Park, Montana
Pullman WA Plant Materials Center
Corvallis Oregon Plant Materials Center
Reproduces sexually by seed.


Notes: Containerized material is best planted in fall while dormant.


References:
Baldwin, B.G., S. Boyd, B.J. Ertter, D.J. Keil, R.W. Patterson, T.J. Rosatti, and D.H. Wilken (eds). 2004. Jepson Online Interchange for California Floristics. Berkeley, CA: University and Jepson Herbaria, University of California. Accessed 7/18/09 online at http://ucjeps.berkeley.edu/interchange.html

Chuang, Tsan-Iang. 1970. A Systematic Anatomical Study of the Genus Perideridia (Umbelliferae-Apioideae). American Journal of Botany 57:495-503.

Craighead, John J., Frank C. Craighead, and Ray J. Davis. 1963. A Field Guide to Rocky Mountain Wildflowers. Boston, MA: Houghton Mifflin Co.

Piper, C.V., and R.K. Beattie. 1914. The Flora of Southeastern Washington and Adjacent Idaho. Lancaster, PA: Press of the New Era Printing Company. 296 p.

Schlessman, M.A., and F.R. Barrie. 2004. Protogyny in Apiaceae, Subfamily Apioideae: Systematic and Geographic Distributions, Associated Traits, and Evolutionary Hypotheses. South African Journal of Botany 70:475-487.

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

USDA, NRCS. 2009. The PLANTS Database. Baton Rouge, LA: National Plant Data Center. http://plants.usda.gov, 19 July 2009.



Links:
Plant Profile from the USDA PLANTS Database
Species information from the University of Washington Herbarium