Common Bird’s Nest (Crucibulum laeve) is called that because it looks like a bird’s nest with several eggs. It occurs on all continents except Greenland and Antarctica. It may be the most common bird’s nest fungus in Canada and the northern two-thirds of the United States. It grows on sticks, wood chips, humus, vegetable debris, and manure. Although common, its small size makes it difficult to see.
The fruiting body is a very small bowl-shaped “nest” containing several tiny, egg-like capsules. When young, it is yellowish, densely hairy, and topped with a yellowish lid. Eventually, the outer surface sloughs off and the lid ruptures and disappears. The mature mushroom has a hairless, brown, shiny, outer surface, and a smooth, white inner surface. Inside the hollow nest are several tiny, white, circular, flattened capsules (eggs). The eggs are attached to the side of the nest by a long, thin, elastic, white cord that can be seen only with a hand lens, a needle, and a lot of patience. The eggs are disbursed by raindrops and wind. Common Bird’s Nest may be edible but is too small and tough to be worth the effort.