Cryptic globe fungus

[CRYPTOPORUS VOLVATUS]

Not long after a pine tree dies, especially if it has been burned in a forest fire or killed by beetles, its surface may take on a blistered appearance as dozens of curiously shaped “puffball mushrooms” sprout from the bark. Because the shiny, lacquered outer surface hides a mysterious inner chamber, this fungus (technically a polypore) is also called pouch fungus and veiled polypore. As the fungus nears maturity, the floor of the inner chamber opens a trapdoor that admits tiny black bark beetles. The insects feast on fungal tissue, and while scrambling around the chamber, end up dusted with spores. When the beetles finally crawl out the trapdoor and burrow into healthy trees to lay their eggs, they inadvertently help fungal spores get past a trees’ shield of tough, defensive bark. Globe fungi often sprout directly out of beetle holes.

*

NATURAL HISTORY

Tucked beneath the fungal body, the inner chamber is a fascinating structure. Its ceiling is pockmarked with thousands of pores that rain spores down onto the floor of the inner chamber and onto any beetle walking to and fro. Each fungus produces an estimated 4.5 billion spores.

*

KEY CHARACTERISTICS

One of the few fungi that can be found during summer; usually creamy to tan yellow, and about 2 inches across.