LIFE HISTORIES AND DEMOGRAPHY OF SHADE‐TOLERANT TEMPERATE FOREST HERBS: A REVIEW

Abstract

Information is reviewed on the life histories and demographic patterns of shade‐tolerant herbs of temperate deciduous forest. Most of the species that have been studied are deciduous perennials. These species generally have a juvenile (non‐flowering) period of several years followed by an extended period of flower and seed production. About half the species reviewed are self‐incompatible, the others are at least partially self‐compatible. Although vegetative reproduction is common, replacement does not always occur by vegetative spread; many species appear to be able to replace themselves by seed. Sexual reproductive effort ranges from 1–5 to 50 % among the species reviewed; seed weight averages 2–6 mg. Short dormancy periods (one season) are most common, with germination rates generally below 50%. Mortality rates of small plants are high, but decline as plant size increases. ‘Ageing’ does not appear to occur. No information exists on population growth rates of temperate deciduous forest herbs, or on the temporal stability of their population sizes or structures. The transition matrix model is suggested as a promising approach to future studies in plant demography.