November 2022 State of LA Fungi
Monday, November 29th at 6:30 p.m.
Online discussion using Zoom
Discussion Leader: Rudy Diaz
Program: "Discussion of the mushroom habitat in the Los Angeles area"

The general takeaway from Tuesday's meeting was that mushrooms are involved in numerous complex interactions which we are still barely starting to understand, making it all the more important to document the plants, fungi, and perhaps even animals in the vicinity.

Historically, the ecological roles of mushrooms have been lumped into three discrete categories saprotrophic, mycorrhizal, or parasitic but it is more appropriate to appreciate fungal lifestyles (like any complex biological trait) on a continuum.

Furthermore, to assess the actual ecological functions of fungi requires specific and focused scientific investigation; however, most claims that X species is saprotrophic and Y species is mycorrhizal are based on superficial observations of context. An example we discussed comes from a recent paper in Current Biology, in which, among several interesting discoveries, the authors shed light on the ecology of "earth tongues" (Ascomycete family Geoglossaceae). The sporocarps of many Geoglossaceae species emerge from logs, which had led mycologists in the past to assume that they were accessing nutrients by decomposing the wood. However, in-depth analysis of the gene content of these species indicates that they actually lack the enzymes necessary for such chemical processes; instead, their reduced genomic toolkits resemble those of other mycorrhizal species, suggesting that instead of being decomposers, they are actually involved in mutualistic relationships with mosses that also inhabit these logs!

There are many such cases of mushrooms defying our assumptions, but the point here is that observations that seem irrelevant today may offer key insights as science progresses.

As always, we strongly recommend you document your finds on iNaturalist, following these tips for how to take photos of mushrooms for identification.

Here are some links posted in the chat during the discussion:

Fungi Of Temperate Europe Wheels

Common Trees of LA

Field Data Slips

Another illustrated Glossary of features and terms (requires Mushroom Observer login)

Tricholoma fracticum in Tustin 11/27/2020 - dozens, barcoded

Article - Terrestrial and Lignicolous Macrofungi article with the BEST, easiest to use diagrams of descriptive fungal terms

One on MushroomObserver, from NM

Mycoweb Boletes