Barometer earthstar

No. Mature specimens are tough, leathery and tasteless, and young ones can be confused with poisonous earthballs, so they should not be picked.

It is not known to be poisonous itself. The danger lies in mistaking the closed young balls for poisonous earthballs.

Its rays react to humidity: they curl inwards over the ball in dry weather and open again after rain or dew.

Cut it in half: an earthball is purple-black inside when young and its skin never splits into rays. The earthstar's outer skin splits into thick rays around a thin-walled inner sac.

On sandy, stony, dry soils, usually near pines and oaks; along paths and in scrub.

Its fruit body lasts for months, so it can be found all year; our Turkish records run from December to April.

Our map data has 15 records from Muğla, Kırklareli, Manisa, Afyonkarahisar, Ankara, Antalya, Denizli and Istanbul.

Its Turkish name on iNaturalist is çatlak yer yıldızı; people usually search for it as yer yıldızı mantarı.

It looks like one, but it is not a true earthstar. True earthstars belong to the genus Geastrum; the barometer earthstar (Astraeus) is closer to boletes, and its rays open in wet weather and close when dry.

The collared earthstar (Geastrum triplex) is a different species from the barometer earthstar. Its outer skin splits into rays and often leaves a collar-like saucer under the central spore sac. It grows in leaf litter and is not eaten.

Usually. 'Star mushroom' and 'star-shaped mushroom' most often mean an earthstar: the outer skin splits into star-like rays around a puffball-like spore sac. The barometer earthstar is one of them; most other earthstars belong to the genus Geastrum. None of them are eaten.

In our calendar, barometer earthstar season runs Mar–Apr, Dec–Jan. The barometer earthstar's fruit body lasts for months, so it can be seen all year; our Turkish records fall between December and April, most of them in January.

On sandy, stony, lime-free and dry soils; it forms partnerships with trees such as pines and oaks. It grows singly or in small groups on path edges, in open woodland and in scrub.

Our map data (GBIF and iNaturalist) holds 15 Turkish records, mostly from Muğla and Kırklareli, plus Manisa, Afyonkarahisar, Ankara, Antalya, Denizli and Istanbul. They cluster on the dry, sandy slopes of the Aegean and Mediterranean regions.

Barometer earthstar can be confused with common earthball (Scleroderma citrinum, poisonous), earthstars (Geastrum spp., inedible) and common puffball (Lycoperdon perlatum, edible species). Look-alikes are compared on this page.

In Turkish, barometer earthstar (Astraeus hygrometricus) is called Yer yıldızı mantarı; other local names include çatlak yer yıldızı.