Maianthemum canadense Canada mayflower Liliaceae MACA; Bx, bg, br, pb, vc; NY iw; Q a, cu; R, ah, an, ar, bd, bk, cb, cn, d, ev, gb, gr, h, js, k, lp, lt, mc, pm, r, ro, sm, v, t, w, wp, wt;


Maianthemum canadense

Maianthemum canadense.M. B. Gargiullo (ca 2012).

Maianthemum canadense is a perennial monocotyledon; a summer-green herb, 4-15 cm tall; colonial ground cover from slender white rhizomes; often forming carpets; roots associated with vesicular-arbuscular endomycorrhizal fungi (Berliner and Torrey 1989); winter plants with next season’s preformed bud in a small white shoot at the base of old stems (Levine 1995). 

Leaves alternate, stem leaves 1-3, stalk 0-0.5 cm long, blade 3-10 cm long, 2-5 cm wide, leaves directly from rhizome with stalk4-10 cm long, blade often larger (Radford et al. 1968), egg-shaped, tip pointed, base lobed, clasping stem, dark green above, veins parallel to midrib; a summer green herb, leaves live 22 weeks (Hicks and Chabot 1985). 

Flowers white, 0.4-0.6 cm wide, petals and sepals alike, 2 each (tepals) elliptic 0.2-0.3 cm long, stamens 4, shorter than tepals; inflorescence of a terminal raceme 2-5 cm long; blooms May-June, pollinated by insects. Pollen is self-incompatible on flowers within a clone, fruit set depends on pollination between clones (Worthen and Stiles 1988). 

Maianthemum canadense fruit

Maianthemum canadense fruit.M. B. Gargiullo

Fruit fleshy, round, 0.3-0.6 cm wide, becoming freckled with red, turning entirely red when mature; up to 10-15 per infructescence; fruits mature June-Aug., often persistent into winter; 1-2 seeds, 0.2-0.3 cm long, pale tan. Fruit eaten by a few birds and small mammals, foliage eaten by deer (Martin et al. 1951; Rooney 1997).

Wetland status: FAC-.

Frequency in NYC: Frequent. Listed as endangered in NJ and KY (USDA, NRCS 2006).

Origin: Native.

Habitat: Undisturbed, moist woods. Tolerates acid soil down to pH 3.8 (Greller et al. 1990). In NYC found in soil with pH 4.4-5.1 (Gargiullo unpublished data). Often near swamp forest edges with cinnamon fern (Collins et al. 1985; Worthen and Stiles 1988). Obligate shade species. Does most growth and photosynthesis before canopy closure in spring. One of very few plants that can grow under shade of beech trees. Also seen growing under canopy of Aralia nudicaulis colony (personal observation). Requires at least 0.1% sunlight in order to survive (compensation point), cannot use more than 2.5% full sunlight (saturation point) (Hicks and Chabot 1985).