Mushrooms That Grow in Cow Manure

Mushrooms, and fungus in general, are versatile. Saprophytic mushrooms, those that feed on dead materials, can grow in a number of conditions and places. Cow manure is often used in the growth of cultivated mushrooms such as Agaricus bisporus, the mushrooms you find in stores and on your pizza. While not all mushrooms will grow from dung, many are quick to take advantage of the nutrient-rich soil manure creates. However, some mushrooms do prefer such conditions even in the wild and can be found growing on or near manure.

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Saprophytic fungi perform the important task of releasing nutrients from dead matter.

Mycenastrum corium

This puffball grows to about the size of a softball and has no stem. It commonly grows in the western U.S., although it can be found in some eastern areas as well. M. corium loves manure-filled pastures and compost heaps, but can also grow in lawns or meadows. It has a thick white or white-brown skin and is shaped like a ball and cracks as it ages, revealing a brown sub-surface. The interior is white, but turns green and then brown with age. Its edibility remains unknown.

Agaricus subrufescens

These mushrooms grow either in scattered groups or dense clusters in humus, on manure and in compost heaps. It's about 2 to 8 inches and has a round convex or flat cap with small scales. It can be light brown or pink-brown and becomes a darker or red-brown as it matures. It has an odor and taste something like almonds, although the strength of the odor varies. A. subrufescens is edible, however, according to the Cascade Mycological Society, you should never eat wild mushrooms raw, and never drink alcohol when trying a new mushroom for the first time. Different species can cause reactions, and alcohol can strengthen any allergic reaction you might have.

Panaeolus subbalteatus

This mushroom will grow on manure or compost heaps, but can also be found in fields or lawns, or even along the roads throughout the U.S. and Europe. It presents a convex cap in youth, but flattens as it ages. Its skin is dark red-brown when young and moist, but darkens as it dries to a pale brown or tan with a darker ring around the edge of its cap. This mushroom is inedible.

Psilocybe cubensis

Perhaps the most well known of mushrooms that grow from dung, P. cubensis is also called the "cow patty mushroom." It has a large cap and when it is young the cap is yellow-brown, but these mushrooms lighten with age, although they retain a darker brown spot in the center of the cap. When the flesh is damaged, it bruises a blue color. The caps have a sticky film and a sweet smell. Possession of these mushrooms is illegal in the U.S.