The honey mushroom or honey fungus (Armillaria mellea) is a honey- to tawny-brown woodland mushroom that grows in dense tufted clusters at the base of trees and stumps, named for the warm amber colour of its cap. It is widely foraged and eaten across Europe and North America, prized for a firm texture and a savoury, faintly nutty flavour; but like many wild fungi it contains a heat-labile irritant and must always be thoroughly cooked — never eaten raw — and even then a minority of people react to it. To gardeners and foresters the same organism is infamous as an aggressive root-rotting parasite that kills the very trees it fruits upon.