Fun with Fungi Identification

Last night I was pulling weeds out of the sedum that's planted in the living retaining wall across from our condo building. Halfway down the wall, I was surprised to see that a large brown fungus had replaced the greenery in several of the plant niches. 

Example

Whoa! I hadn't walked past the wall for a couple of weeks, but there was definitely nothing there before. Because I wanted to know what I was looking at, I took a photo, then came inside and searched for a website that could help me with identification. The internet suggested the website FungusID, a wild mushroom identification assistant.

The site was easy to navigate. After I uploaded my photo, the page thought for a couple of minutes, then gave me three possibilities: Polyporus umbellatus, Meripilus sumstine, or Clavaria fumosa.  Given that the mushroom was nestled into a niche my photo wasn't great, so even the best option only had an 11.68% chance of success.

Each possibility had options for clicking through to other sites to get more information, which I did. I finally concluded that our wall probably sported impressive-sized specimens of Meripilus sumstinei, commonly known as the Giant polypore or Black-staining polypore. 

Giant polypore normally grows in large clumps on the ground around the base of oak trees and tree stumps, so it's growing location was very strange. However, the landscaping on the top of the wall (which was a scruffy mixture of half-dead trees, bushes, and weeds) was replaced shortly after we moved in. I wonder if there are still oak roots buried underneath the mulch to support the fungus?

Five years ago today: Family Old And New (California, Summer 2018)