7: Cardiocrinum cordatum (Thunb.) Makino (Liliaceae)

Abstract

AbstractThe life‐history characteristics of Cardiocrinum cordatum (Thunb.) Makino (Liliaceae) are described here. This is a unique monocarpic perennial herb of temperate broad‐leaved deciduous forests in the Japanese Islands and adjacent Far East regions. New aerial shoots appear above ground in mid April to early May. Cardiocrinum cordatum comprises distinct growth stages, single‐leaf and multiple‐leaved rosette stages, and then a flowering stage with a large multiflowered inflorescence at the top of the stem. The flowering plants attain 0.7–2.0 m in height and bear several large cordate cauline leaves, and 2–15 laterally blooming, greenish white flowers, 12–18 cm in size, are borne at the top of the straight inflorescence. Cardiocrinum cordatum depends on two reproductive modes, sexual reproduction via seeds and vegetative reproduction forming a few to several bulblets at the base of mother bulbs. The flowers are furnished with large nectar glands at the base of corolla, and the amount of nectar secreted is very high; thus, many bumblebee species are attracted to the flowers. Each flower has 600–670 ovules and produces 393–531 seeds (average 410). The average seed‐setting rate per flower is high at 65–79%. An exceedingly large number of seeds with 4–5 mm thin filmy wings are produced, attaining several thousand (800–6000) in number per plant. Individuals asexually formed have large one‐leaf or multiple‐leaves, and can bypass crucial small juvenile stages with high mortality. In addition, because mature plants die after sexually reproducing once, ramets asexually reproduced can use the large spaces that the mother plants occupied.