Rounded earthstar

Description:

The rounded earthstar is a species of mushroom belonging in the Geastrum genus. It is found growing on rotting wood. It is considered inedible by mushroomers, because of its bitter taste. It is a common mushroom, but collections are at their peak during late summer. The opening of the outer layer of the fruiting body in the characteristic star shape is thought to be due to a buildup of calcium oxalate crystals immediately prior to dehiscence. G. saccatum is distinguished from other earthstars by the distinct circular ridge or depression surrounding the central pore.

Habitat:

G. saccatum is saprobic, and grows scattered or clustered together in leaf litter of humus, usually in late summer and fall. It has a cosmopolitan distribution, and is well adapted to tropical regions

Notes:

These earthstars were deep in the understory leaf litter along side the Tall Trees Walk at Mt. Field National Park. They were are late in their sporing phase, and have lost the clear "star" like edges of the lower structures.