Calvatia gigantea

Names

Giant Puffball, (Calvatia gigantea)

Old scientific names include Lycoperdon giganteum, Bovista gigantea or Langermannia gigantea).

Description

One of our largest fruiting fungi, this species regularly weighs in at 4 kg and occasionally as much as 20 kg. It looks very much like a white football, as it doesn’t have a stem of any kind, growing out of the soil with white root like structures at the base. When fresh, the outer skin is white and smooth and the inside is white with a firm texture. As the fruit body ages, the outer skin becomes increasingly brown and the inside, which is actually the ripening spore mass, changes colour becoming increasingly yellow, then olive and finally brown. The outer layer will finally split open and the millions of ripe spores will be released.

The Giant Puffball is a saprotrophic or ‘recycler’ fungus, which is breaking down dead plant material in the substrate. It will not be damaging the grass in which it grows. Saprotrophic fungi play a vital role in driving the carbon cycle, releasing any nutrients that they do not require back into the habitat.

It is considered an edible fungus when young and white, although some find it rather bland by itself; cooking in bacon fat helps! As well as a food source, this fungus has also been used to staunch blood, smoke out bees and as tinder.

Look-a-likes:

This is a very distinct species. Really the only possible source of confusion is with Lycoperdon utriforme the Mosaic Puffball. This is relatively common in Scottish pastures and can attain the size of a small Giant Puffball. When young, the outer skin is covered with warts, which rub off leaving a mosaic pattern. If you cut the puffball in half, you can see that the sterile base of the Mosaic Puffball is differentiated from the upper fertile spore mass

Fruiting

From early summer to autumn

Habitat

On soil in parks, gardens, grassland, in and around cultivated fields (often in nettle beds or other nitrogenous soils), compost heaps and occasionally open woodland

Distribution

(Checklist of the British and Irish Basidiomycota Legon & Henrici 2005): Scotland (and elsewhere) occasional or infrequently reported. The total number of records for this species on the Fungal Records Database of Britain and Ireland (2012) is 1287 of which 70 are from Scotland. NBN distribution map.

There are a scattering of records from the North East including Chapel of Garioch, Glas Maol, Glen Tanar, Old Aberdeen and Strathorn. With so much agricultural land here, surely this species must be under recorded. It can pop up almost anywhere though as a 2019 discovery at Deanich Lodge (remote East-Ross-shire) testifies. Any records would be much appreciated to help us understand the real distribution of the species.

A North East finding in 2004 created quite a stir in the national press!