Fungus?

[duajones]

Serpentine slime mold it is. A mulch fungus called serpentine slime mold, which frequently develops on shredded hardwood mulch. A lot of people describe it as looking like "dog vomit."

This slime mold is a naturally occurring organism because it feeds on decomposing bark on downed trees and other organic matter.

It's not harmful to plants, just an unpleasant looking glob. It eventually dries into a mass-like powder. Resist the urge to blast it with water or yank it away because it will release thousands of fungal spores into the air. Those spores will settle somewhere and potentially develop.

Instead, you can turn the mulch over so you don't have to look at it. Do so carefully.

Or, scoop the fungus with a pitchfork or shovel, put it in a plastic bag and discard in your trashcan for disposal. There is no good reason to use any chemical fungicide on the organism. In reality, these organisms are good because they break down stuff in a healthy way, sort of like earthworms. When weather conditions are right, the fungus will stop growing.