 Astraeus hygrometricus is an ectomycorrhizal fungus and grows in association with a broad range of tree species . The mutualistic association between tree roots and the mycelium of the fungus helps the trees extract nutrients ( particularly phosphorus ) from the earth ; in exchange , the fungus receives carbohydrates from photosynthesis . In North America , associations with oak and pine are usual , while in India , it has been noted to grow commonly with chir pine ( Pinus roxburghii ) and sal ( Shorea robusta ) . The false earthstar is found on the ground in open fields , often scattered or in groups , especially in nutrient @-@ poor , sandy or loamy soils . It has also been reported to grow on rocks , preferring acid substrates like slate and granite , while avoiding substrates rich in lime . In Nepal , fruit bodies have been collected at elevations of 3 @,@ 000 m ( 9 @,@ 800 ft ) . Fruit bodies typically appear in autumn , although the dry fruit bodies are persistent and may last up to several years . Gelatinipulvinella astraeicola is a leotiaceous fungus with minute , gelatinous , pulvinate ( cushion @-@ shaped ) apothecia , known to grow only on the inner surface of the rays of dead Astraeus species , including A. hygrometricus . 
