Germination ecology of Galeopsis bifida (Lamiaceae) as a pioneer species in forest succesion.

Abstract

The occurrence of on clear-cut and burned forest soil and its disappearance in 4–6 years after disturbance is attributed to its germination ecology. Initially the seeds are dormant 96–100% and remain dormant in nylon gaze bags in different types of forest humus layers at least 10 years. Dormancy is released in laboratory (1) by treatment of 100 ppm aqueous solution of GA, (2) by heating the dormant seeds to 40–55°C for 1–5 h, and (3) by 1% KNO solution. It is concluded that conditions in clear-cut and burned areas favour germination of seeds in regard to temperature and content of nitrates in contrast to humus of closed vegetation where the seeds remain dormant.Caleopsis bifida33