Maianthemum dilatatum



The Basics

Taxonomy: Kingdom - Plantae (plants). Subkingdom - Tracheobionta (vascular plants). Superdivision - Spermatophyta (seed plants). Division - Magnoliophyta (flowering plants). Class - Liliopsida. Order - Liliales. Family - Liliaceae (Lily Family). Genus -Maianthemum F.H. Wigg. Species - Maianthemum dilatatum (Alph. Wood) A. Nelson & J.F. Macbr

Ecology: A shade-tolerant and ocean spray-tolerant, submontane to subalpine, Western North American forb distributed more in the Pacific than the Cordilleran region. Occurs in cool mesothermal climates on very moist to wet, nitrogen-rich soils (Moder or Mull humus forms); its occurrence decreases with increasing elevation and continentality. Scattered to plentiful in coniferous and broad-leaved for­ests on water-receiving and water-collecting sites, commonly found on stream-edge sites, floodplains, and sites affected by ocean spray. Grows with Blechnum spicant, Polystichum munitum, Tiarella trifoliata, Trautvetteria caroliniensis, and Lysichitum americanum. Characteristic of alluvial floodplain forests.


Plants: Perennial herbs from wide-spreading rhizomes, units 8–20 cm Χ 1–1.5 mm, roots restricted to nodes. Stems erect, 1-3.5 dm tall. Leaves: solitary on sterile shoots, 2–3 on fertile shoots, petiolate; blade cordate, 6–10 Χ 5–8 cm; base lobed, with deep sinus; apex sharply acute; proximal leaves short-petiolate, blade triangular to cordate, petiole 4–7 cm; distal leaves petiolate, blade deeply cordate, petiole 7–10 cm. Flowers: Inflorescences racemose, complex, 15–40-flowered. (1–)3(–4) per node, 2-merous; tepals conspicuous, 2–3.2 Χ 1.5 mm; filaments 1.5 mm; anthers 0.2–0.4 mm; ovary globose, 0.8–1 mm wide; style 0.4–0.5 mm; stigma distinctly 2-lobed; pedicel 3–5 Χ 0.2–0.4 mm. Berries: Fruit a red berry, globose, 5 mm. long, few-seeded.


Due to temperature differences this species requires colder temperatures in the spring to allow proper growth. If the temperature was above 15 to 10OC then the species will have leaves that do not last for a long time. This temperature also affects the percentage of flowering plants on the species. The colder temperature allows the species to sprout and grow. The colder temperature makes the species sprout and produce leaves.


Maianthemum dilatatum flowers from early spring into summer from May to July. In this time the flowers can over produce the pollen and cause a self pollen to occur. Pollination also occurs from insects such as bugs and beetles. Germination: The Germination of these seeds require a cold temperature to allow them to grow. Seeds need 4 months or longer to germinate in moist dark conditions. Once that period has ended roots will appear in 1 to 2 months

Species Distribution


E-Flora of British Columbia
In Klinkenberg, Brian. (Editor) 2015. E-Flora BC: Electronic Atlas of the Plants of British Columbia []. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 06/02/2017 10:50:30 AM ]

USDA Plants Database
USDA, NRCS. 201. The PLANTS Database. National Plant Data Team, Greensboro, NC 27401-4901 USA.
Distribution Map photo credit

Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria. [web application]. 2017. Berkeley, California: The Calflora Database [a non-profit organization].

Flora of North America
Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 19+ vols. New York and Oxford.

Effects of Growth Temperature and Winter Duration on Leaf Phenology of a Spring Ephemeral and a Summergreen Forb
Yoshie, F. (2008). Effects of growth temperature and winter duration on leaf phenology of a spring ephemeral (Gagea lutea) and a summergreen forb (Maianthemum dilatatum). Journal of plant research, 121(5), 483-492.

Seed germination Characteristics of Maianthemum dilatatum
Kawano, H., Kanazawa, Y., Suzuki, K., & Ohara, M. (2020). Seed germination characteristics of Maianthemum dilatatum (Wood) Nels. et Macbr.(Asparagaceae). Plant Species Biology, 35(1), 38-48.

Opportunities for Geitonogamy in the Clonal Herb Maianthemum dilatatum
Wilson, A. S., Van der Kamp, B. J., & Ritland, C. (2005). Opportunities for geitonogamy in the clonal herb Maianthemum dilatatum. Botany, 83(9), 1082-1087.

Burke Museum of Natural History and Culture
Burke Museum. 2017. Maianthemum dilatatum [Online]. University of Washington.
Photo credit: 2004, Ben Legler