23. Trillium L. (trillium, wake robin)
(Case and Case, 1997)
Plants perennial, with usually short rhizomes, lacking the odor of onion or
garlic. Aerial stems unbranched below the inflorescence, erect or nearly so,
glabrous or sometimes slightly scabrous. Leaves a single whorl of 3 (4 or 5 in
aberrant plants) at the tip of the aerial stem, narrowly to broadly ovate or
elliptic, glabrous (sometimes with minute, hairlike, scabrous outgrowths near
the base along the undersurface veins). Inflorescences of a single flower at
the tip of the aerial stem. Flowers sessile or stalked, not subtended by
bracts, none of them replaced by bulblets. Perianth with the sepals and petals
free, the sepals herbaceous and green, sometimes reddish tinged, the petals
white, pink, maroon, brick red, or greenish yellow, rarely yellow or green.
Stamens 6, free, erect. Styles 3, the bases erect and sometimes fused, the
upper portions elongate, spreading, the stigmatic areas along the inner sides.
Ovary superior, with 3 locules, each with 4–10 ovules, 3- or 6-angled, ribbed
or winged. Fruits berries, 8–25 mm long, ovoid to ellipsoid, the tips beaked
with the persistent styles. About 50 species, North America, Asia.
Some species of Trillium were used historically in herbal medicine, but
the most common use of the genus is as ornamentals in the shade garden. The
species are relatively difficult to grow from seed; plants must be several
years old before they will flower. Consequently, many of the plants sold at nurseries
have been excavated from natural populations by unscrupulous collectors. This
has adversely affected several of the species and the habitats in which they
grow. Because of this and because many such plants were excavated without
proper care and will not survive transplantation, gardeners are urged to become
aware of the sources for their plants and to insist on nursery-propagated
plants grown from seeds or rhizome divisions of cultivated stocks.