Flowering and individual survival of a population of the grass Brachypodium sylvaticum in Nåtö, Åland Islands, SW Finland.

Abstract

A population of the grass Brachypodium sylvaticum (Hudson) Beauv., located in and outside a permanent quadrate (size 2 × 2 m) in a dense Corylus stand, was studied from 1964 to 1984. Each individual (tuft) was marked and the culms with spikelets counted every year. The vegetation of the quadrate, and the soil in its vicinity, were studied. During the study the population increased from four tufts with only one culm in one tuft in 1964 to more than 80 tufts with more than 3 000 culms in 1984. The succession of the vegetation revealed that the graminids increased continuously, especially after 1983, when all trees and shrubs were cut. The earliest observed tufts were still alive in 1984. The annual mortality of the tufts was absent, or very low during most of the time. It is suggested that B. sylvaticum is principally a stress-tolerant competitor.