As a measure to conserve water, i use hardwood mulch around my beds. Lately we’ve had a prolonged stretch of damp weather accompanied by overcast, and the mushrooms are putting up their fruiting bodies thanks to the conditions. The mycelial threads are in the mulch, doing the work of decomposing the wood chips. The part in the pics is producing spores, since apparently conditions are favorable right now.
some ephemeral mushrooms growing in the mulch
I took the photo (and a whole stack of others) in the morning, and by evening the sunlight had obliterated the fruiting bodies. This stand was the most dense and prolific, although they were almost everywhere I had hardwood mulch. A few different types popped up in the lawn as well, but this was the coolest picture out of the batch.
It was daylight, so I can’t say for sure, but these did appear to luminesce faintly.