Parasitic Fungi

The world’s largest living organism is a honey mushroom like this one pictured here. This massive honey mushroom is a parasitic mushroom and covers over 2,300 acres in the Blue Mountains of Oregon.
The world’s largest living organism is a honey mushroom like this one pictured here. This massive honey mushroom is a parasitic mushroom and covers over 2,300 acres in the Blue Mountains of Oregon.

NPS

My goodness what’s with all the mushroom jokes?! I don’t know, but they’re growing on me! 

Parasitic fungi, like mycorrhiza fungi, also form symbiotic relationships with other organisms. But while mycorrhiza fungi form mutualistic relationships with the redwoods, a situation where both organisms benefit, parasitic fungi form relationships where only the fungi benefit, and the host is harmed. 

Much like saprophytic fungi, parasitic fungi also get their nutrients by decomposing organic material. However, parasitic mushrooms will break down the organic material of still living species, while decomposers break down the organic material of dead things. Some species, like the honey mushroom can be classified as both a decomposer or a parasite, depending on conditions! You can find the honey mushroom here at Muir Woods on hardwood trees like the tanoak. Thankfully, they do not affect our coast redwoods. Redwoods have high levels of tannic acid in their bark which protects the trees from infections and things like parasitic fungi. 

For Further Reading:

Dreskin, Wendy. “Marin Hike: November Brings All Sorts of Fungi Drama.” Marin Independent Journal, Marin Independent Journal, 16 Oct. 2019, www.marinij.com/2019/10/20/marin-hike-november-brings-all-sorts-of-fungi-drama/.

“Parasitic Fungi.” National Parks Service, U.S. Department of the Interior, www.nps.gov/mora/learn/nature/parasitic-fungi.htm.

“Parasitism in Plants and Insects.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., www.britannica.com/science/fungus/Parasitism-in-plants-and-insects.

Patton, Vince. “Oregon Humongous Fungus Sets Record As Largest Single Living Organism On Earth.” Opb, OPB, 2 June 2020, www.opb.org/television/programs/oregon-field-guide/article/oregon-humongous-fungus/.

Last updated: September 16, 2021

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