Description

Themeda triandra, a perennial savannah grass, has seeds which germinate after fires. The seed is buried by hygroscopic movements of the awn to a mean depth of 1 cm, where it is protected form the heat of fires. Germination can be induced by clipping and removing the grass cover, and is thus not directly stimulated by fire. Field and laboratory experiments suggest that germination is induced by a combination of light and high temperatures, which is produced by cover removal. Awned grasses are widespread in regularly burnt grasslands, and seed burial and post-fire germination, if found to be widespread, could be important in grassland management.