It causes a white rot in various types of broadleaved trees, particularly beech (Fagus), but also Abies, Picea, Pinus, Quercus and Ulmus species.

In the field, it is recognizable by the large, multi-capped fruiting body, as well as its pore surface that quickly darkens black when bruised or injured.

[4] The giant polypore was previously considered inedible, due to its very coarse flesh and mildly acidic taste,[5] but more recent sources list it as edible.

[4] Also, it may be mistakenly consumed because of its resemblance with the edible species commonly known as Hen of the Woods (Grifola frondosa) which is regarded as much better tasting.

According to Ryvarden and Gilbertson in their monograph on the polypores of Europe, M. giganteus grows especially on Quercus and Fagus tree species, but it has also been collected on the hardwoods Acer, Aesculus, Alnus, Betula, Castanea, Celtis, Corylus, Eucalyptus, Laurus, Myrica, Persea, Pittosporum, Platanus, Populus, Prunus, Pyrus, Tilia, Ulmus; it has also been found growing on the coniferous species Abies, Larix, and Pinus.

[3] Bondarzewia berkeleyi or "Berkeley's polypore" is often confused with M. giganteus (or M. sumstinei) in eastern North America but can be distinguished by its lack of black-bruising and much larger pores.