The Destroying Angel (Amanita bisporigera) is a rather elegant looking mushroom, sporting all white on all its features. This mushroom belongs to a group of fungi called Amanitas, which the majority possess: a cap, sometimes with patchy warts, gills that are often pale, crowded, and free from the stem, white spore prints, stems with a ring zone and an enlarged base (sometimes cup-like) called a volva. Many members of this group are toxic if consumed, and a handful of them are deadly toxic. The Destroying Angel is one of the subsets that is fatal when eaten. Though amanitas can be rather tough to identify, A bisporigera is an exception.
Amanita bisporigera is a relatively medium-sized mushroom with a white cap, but unlike most amanita mushrooms, this one lacks the patches on the cap surface. With age, the top center may discolor slightly. Underneath the cap is a series of crowded white gills that are frequently short near the outer margins. The gills are free from the stem. The stem is white, often tapering slightly towards the cap. Attached towards the top is a white skirt-like veil and below that, the stem can be fairly smooth or shaggy. The base of the mushroom (sometimes buried) is a white sac-like volva. The spore print is white, like most amanitas. With the morphological features considered, Amanita bisporigera can be further separated from its two closely related sister taxa (also named Destroying Angels) with chemical reactions. In this instance potassium hydroxide (KOH) turns bright yellow when in contact with the cap surface. This reaction occurs only with this species of Destroying Angel and not the other two.
Destroying Angels can be found in the summer and early fall months, growing from the soil near oak trees and potentially other hardwoods. In my experience at Indian Cave State Park, I find them growing near northern red oak (Quercus rubra) and black oak (Quercus velutina) trees in more open woodlands, or woodland edges.
Contrasting from the Destroying Angel, the Deadly Galerina (Galerina marginata) is a small sized brown mushroom. Many different mushrooms share similar features with Galerina marginata making it hard to differentiate between them, thus they have been grouped into a category called the Little Brown Mushrooms (or LBMs. Sometimes LBMs need the aid of a microscope to confidently ID them. Many of these LBMs are edible or harmless, while some are toxic and hallucinogenic, and a few are deadly toxic. Because of their similarities in characters and variable effects following consumption, LBMs are not for beginners and should be considered when foraging for mushrooms.
To distinguish Galerina marginata from other little brown mushrooms, several identification criteria should be met. As previously mentioned, these mushrooms are small, but not tiny, and brown. Their caps are light brown when fresh, becoming cinnamon brown later and tend to be sticky when moist. Caps can dry out creating different zones of brown color (hygrophanous). The cap margins can be slightly lined (striate) upon maturity. Underneath the cap, the gills are attached or slightly running down the stem. The gills are light brown, sometimes covered in partial veil, becoming rusty brown with age, close to nearly distant with frequent shorter gills. The stem is dry, usually covered with flattened, whitish fibrils over a brown to dark brown base color. The base of the stem is often coated in white mycelium with a delicate, with a white to rusty brown colored partial veil that may disappear towards the top. The spore print is rusty brown. According to some sources, potassium hydroxide on cap surfaces can result in reddish reaction while I have yet to observe this in the field.
Deadly Galerinas can be found year-round, but in the Midwest, they are usually found during the colder temperatures in the spring and fall. I have seen it in the presence of snow at Indian Cave State Park. They tend to grow scattered in groups or in clusters on dead deciduous and coniferous wood.
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