Pear-shaped puffball

Description:

Lycoperdon pyriforme, commonly known as the pear-shaped puffball or stump puffball, is a saprobic fungus present throughout much of the world. Emerging in autumn, this puffball is common and abundant on decaying logs of both deciduous and coniferous wood. The fruiting body of the pear-shaped puffball measures 1.5 to 4.5 cm in width by 2 to 4.5 cm in height. They are often pear-shaped as the name suggests, but they may also be nearly spherical. When very young they are covered in small white spines that typically fall off before maturity. A small developing pore may be visible at the top, while the sterile base of the mushroom is small and appears to be pinched in. Colour ranges from nearly white to yellowish brown with the darker shades developing with age. The central pore ruptures at late maturity to allow the wind and rain to disperse the spores. The base is attached to the wood by means of rhizomorphs (thick, cord-like strands of mycelium). The gleba, or inner spore mass, is white when young, but it becomes greenish-yellow to dark olive-brown with age. The spores measure 3 to 4.5 µm and are round, smooth and a dark olive-brown in color.

Habitat:

Decayed log in woods (could not identify log, but the surroundings are mostly maple and oak)

Notes:

Puffball mushroom with dark green spores on a dead log along the Des Plaines river trail.