Puffball Mushrooms Round, stemless fungi that release spores in dusty clouds
Puffballs are the simplest mushrooms to recognize: round or pear-shaped, with no cap, no stem (or just a rudimentary base), and no gills or pores. Spores develop inside the fruitbody in a mass called the gleba. When mature, the outer skin opens or tears, and the powdery spore mass is released — often in a visible “puff” when the fruitbody is bumped or struck by rain.
Several puffballs are good edibles when young and the interior is firm and pure white. The critical rule: always slice them in half before eating. If the interior shows any color or any internal structure (gills, a developing cap), it isn’t an edible puffball — it could be a developing Amanita egg, which includes deadly species. Earthballs (Scleroderma) are also puffball-like and toxic, and especially dangerous to dogs.
Scout Puffball Habitat on Forayz
Giant puffballs favor open grasslands and sagebrush on the east side. Gem-studded puffballs prefer forest trails and roadsides. Use ecoregion and public land layers on Forayz to locate productive habitat. Free with a Forayz account.
Notable PNW Species
Gem-Studded Puffball — Lycoperdon perlatum
The most common puffball in PNW forests. 1–5 cm across, 1–7 cm tall, pear-shaped, covered in conical spines (the “gems”) that fall off leaving a net-like pattern on the surface. Prefers disturbed ground — trail edges, roadsides, logging roads — but also found in duff and on well-decayed wood. Widespread and common, fruiting in fall. Edible when the interior is firm and pure white. The spines easily distinguish it from earthballs.
Pear-Shaped Puffball — Apioperdon pyriforme
Often abundant, especially in northern Cascadia. 2–6 cm tall, pear-shaped, beige to warm brown, granular to smooth rather than spiny, with conspicuous white cords at the base. Grows in clusters on rotting logs, stumps and buried wood — not in soil like the gem-studded puffball. Fruits mainly in fall. Edible and one of the better small puffballs, but only when completely white inside: once the spores start to mature (yellowish to olive), it can cause stomach upset.
Western Giant Puffball — Calvatia booniana
One of the largest mushrooms in the PNW: a flattened ball 20–50 cm across and 10–25 cm tall, whose skin soon cracks like dried mud. Look in open forest, grassland and sagebrush country. It belongs mainly to the dry east side; west of the Cascades it turns up only now and then, in the Willamette Valley and other rain-shadow areas, and not at all where it is wet. Fruits in late spring and summer. A very good edible while young and firm, with a pure white interior; eat only specimens with no discoloration.
Sculptured Puffball — Calbovista subsculpta
About softball-sized (5–15 cm), white at first, with a thick skin that breaks into blunt, pyramid-shaped patches, turning yellowish ocher and then brownish with age. Found in open east-side forest, high meadows and disturbed ground, in spring and early summer. Edible while young, if pure white inside.
Smoky Puffball — Calvatia fumosa
A flattened ball 2–8 cm across with a thick, rind-like skin, white at first, then blotched with gray. Often half-buried in duff beneath mountain conifers, and common in the high Cascades and in east-side forest. Fruits in spring and summer. Named for its foul smell, which develops soon after it emerges — a mix of rotten eggs, propane and outhouse. Edibility unknown.
Bovista / Tumbling Puffballs
Small (1.5–4 cm), round and lightweight, with a thin outer skin that peels away to expose a smooth inner skin. When mature they often break loose and tumble in the wind to spread their spores. In grassy areas, meadows and lawns, fruiting through the warmer months, especially where irrigated. Several species occur in the PNW, most needing a microscope to identify. Edible when young and white inside, but too small to be worth collecting.
Earthstar — Geastrum saccatum
A puffball-like spore sac sitting in a bowl atop 4–9 star-like rays that split open and curl back, lifting it off the ground. 3–7 cm across when open. In duff under conifers, fruiting in fall and early winter, though the fruitbodies persist year-round. Striking and unmistakable in form; edibility unknown. Several Geastrum occur in the PNW, most going by European names that haven’t been checked against western specimens.
Dye-Maker’s False Puffball — Pisolithus arhizus group
Rounded to club-shaped, 4–12 cm across, with a rough, unappealing exterior (also called dead man’s foot). Cut young, the interior is a mass of multicolored grains that mature into brown powder. Grows in poor, disturbed soil — roadsides and under young planted trees — with birch and oak in towns and with pines in the wild, often fruiting in summer even without rain. Inedible. The powdery spores repel water and can set off sneezing fits. Prized by fiber artists for lightfast dyes.
Earthballs — Scleroderma (toxic)
Round to cushion-shaped, 2–8 cm, with a thick, tough skin, very firm flesh, often a tuft of cords at the base, and an interior that turns purplish black. Toxic, causing severe gastrointestinal illness — and especially dangerous, sometimes fatal, to dogs, which seem to like eating them. Several species occur here, many introduced with planted trees such as birch and linden in towns and parks.
Always Slice Puffballs in Half
Before eating any puffball, cut it vertically through the center. The interior must be uniformly white and firm with no internal structure visible — no developing cap, gills, stem, or colored zones. A developing Amanita button (egg stage) can look like a small puffball on the outside but will show the outline of a mushroom inside. Amanita phalloides and A. ocreata are deadly.
Earthballs (Scleroderma) are toxic puffball look-alikes: a thick, tough skin, very firm flesh, and an interior that turns purplish black. If in doubt, don’t eat it.
An earthball (Scleroderma citrinum) cut open: thick skin, dark interior. Not a puffball. Photo: Drew T. Henderson / iNat / CC BY-SA
The White Interior Rule
Any discoloration inside means the spores have started to mature: yellow, olive, brown or purple tints. Only eat puffballs that are uniformly white and firm when sliced. Past that point they’re not just worse eating — maturing pear-shaped puffballs, for example, can cause stomach upset.
Find East-Side Habitat for Giant Puffballs
Calvatia booniana grows in the drier climates east of the Cascades. Use the ecoregion layer on Forayz to explore sagebrush-steppe and dry forest zones where this species fruits in late spring and early summer.
Habitat & Season
Puffballs occupy diverse habitats. The gem-studded puffball grows on trail edges, roadsides and disturbed ground, and in forest duff; the pear-shaped puffball on rotting wood. The western giant and sculptured puffballs are open-country species of the east side and high meadows, the smoky puffball grows under mountain conifers, Bovista in grass and lawns, and earthstars in forest duff. Seasons differ: Lycoperdon, the pear-shaped puffball and earthstars fruit mainly in fall, while the giant, sculptured and smoky puffballs fruit in spring and summer. Old, spent fruitbodies of several species persist into winter.
Sources: Mushrooms of Cascadia (Siegel & Schwarz, 2024); MycoMatch (© Ian Gibson), a compilation of published descriptions through which most other field-guide authors named here are quoted.