Fungus P.I. Tree Health Detective

This year NC State Parks is celebrating the Year of the Tree, and we at Lake James State Park are excited to be part of the celebration. We love our trees, even conducting prescribed burns to help native trees, such as hickories and Table Mountain pines, thrive, and we are often on the lookout for hazard trees, photogenic trees, and even champion trees.

For those of us who did not study forestry at school, though, it may be hard to determine how healthy a tree really is. We may assume the best if green leaves shade the trails and if no lightning scars suggest weather-related trauma. An interesting forest ally can help us know the full story, though. Without speaking, a fungus can tell us more about the plants around it than one might think possible.

For instance, take a look at these American Caesar mushrooms (Amanita jacksonii). These beauties bring color to the forest floor, and while many mushrooms in this family are poisonous to humans, they are quite beneficial to trees. Trading their minerals and other nutrients for a tree’s carbohydrates, the American Caesar is a flashy indicator of good forest health.

Another indicator of healthy trees is the appearance of Dead Man’s Fist (Pisolithus arhizus). Sure, the nickname is creepy, but seeing this weird puffball means healthy trees are nearby. These mushrooms fruit in odd places, such as amongst gravel or through asphalt, and they form a symbiotic or mutually beneficial relationship with trees.

On other hand, the Jack O’Lantern mushroom (Omphalotus illudens) is a harbinger of doom. Fruiting around Halloween, these mushrooms are a fun find, owing to their bright orange color and green spores that glow in the dark. If you find these poisonous mushrooms in the woods, though, they are most likely attached to a tree that is dying (or already dead).

Likewise, the Hemlock Polypore (Ganoderma tsugae) indicates poor tree health in the vicinity. As the name suggests, these mushrooms grow on hemlock trees, or rather, dying hemlock trees. We have lost many Hemlock trees to the woolly adelgid, and the Hemlock Polypore mushrooms sometimes serve as gravestones for once majestic trees.

So, when you visit the park this summer, be sure to look up to appreciate the towering trunks and leafy branches of the many trees protected therein. But also look down to see what forest prognosis our fungal detectives might be sharing.