Phenology of a temperate fern Dryopteris wallichiana (Spreng.) Hyl. (Dryopteridaceae) in Uttarakhand, India

摘要

Initiation and proliferation of leaf primordia, leaf expansion and maturation of a basket fern Dryopteris wallichiana are described based on two years of observation. The phenology of these events is strictly seasonal beginning with the onset of spring in the temperate Himalayan climate. Leaf primordia initiated during late summer often remain dormant but expand in the next growing season. Maturation of most of the leaves of a growing season is completed before the start of winter, but these withstand the winter cold. Leaves of the previous growing season remain erect on the rhizome for about 20 months after which they collapse. Significance of the presence of green and dry collapsed leaves on the rhizome is discussed.