What is that? A simple question leads Naturalists down a road of curiosity, questions, and with a bit of skilled practice, answers. When an organism is identified it opens the door, takes on meaning, and hopefully allows a student to dig deeper. While leading a school group along West Channel Pond nearby Rocky River Nature Center, a student pointed to a snag (standing dead tree) and said, “What is that?” He wasn’t asking about the tree itself. Something appeared to be attached directly to the tree trunk. The bark had fallen off and exposed the unknown organism. Is it simply attached, or growing? I quickly concluded A) it’s awesome, but B) I don’t know what it is. The hike moved on, but the interest stuck with me. Something told me this “thing” is alive!
|Armillaria root rot (a.k.a. black bootlace or shoestring root rot) showing its flattened rhizomorphs (mycelial cords), a hallmark sign that the fungus is present. |
With inquiry on my side and a fiery appetite of curiosity, I learned this unknown organism to be a fungus. Specifically, the string-like bits and pieces (rhizomorphs) are dried remnants honey mushroom.
|Honey mushroom (Armillaria spp.), said to be the largest of all living things. A single organism (Armillaria solidipes) growing in Oregon spreads 3.4 square miles and is over one-thousand years old. |
Fungi are impressively variable in appearance from species to species, but also from individual to individual. As one of the six kingdoms of cellular life, they get a lot of attention. This particular species is considered to be a parasite, causing Armillaria root disease or “shoestring root rot.” Mystery solved. Its hosts include many woody angiosperms (hardwoods) and gymnosperms (conifers). Crown thinning and branch dieback are some of the common symptoms a tree would exhibit if it’s being undertaken by honey mushroom.
Ultimately, fungi do right by our planet. Fungus benefit other organisms in the ecosystem by producing food for humans and wildlife, decomposing organic matter into soil, and by providing nutrients to tree roots. This last benefit is of critical importance, as trees provide our clean breathing-air. A question led me down this path, and an answer kept me moving. You’ve got to love natural history!