Earthstar Gaestrum


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Earthstars, belonging to the genus Geastrum, are aptly named for their star-like appearance when their outer layer splits and peels back, forming pointed “arms” that resemble a star. These unique structures are puffballs, releasing their spores when they’re pressed upon by, for example, falling raindrops.

Earthstar Gaestrum

Common Name
Earthstar Gaestrum

Latin Name



Earthstars can be found worldwide, but are especially common in temperate regions.


Their star-like appearance is their most distinguishing feature. The outer layer (peridium) splits and peels back to reveal a round spore sac. The number of “arms” and how far they recurve can vary by species.


They vary in size from a few centimeters to about 12 cm across, depending on the species.


Earthstars are typically found on the ground in woodlands, often among leaf litter or on decaying wood.


Saprotrophic, meaning they feed on decaying organic matter, especially wood.


Like other fungi, Earthstars begin as spores. The spores germinate and form a network of mycelium. Under suitable conditions, this mycelium produces the puffball-like fruiting bodies. When mature, the outer layer splits, forming the characteristic star shape and revealing the spore sac. The spores are released when disturbed, starting the lifecycle anew.

Defense Mechanisms

While not particularly toxic, the tough and leathery texture of Earthstars makes them unpalatable and generally deters consumption.

Ecological Importance

They play a role in the decomposition of organic material, helping in nutrient recycling within ecosystems.

Conservation Status

While Earthstars are generally common, specific species might be rarer than others. However, as a genus, they aren’t known to be under threat.
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