Black slime in my barkdust, is this a concern?


This is a slime mold, which is a non-pathogenic fungus that feeds on organic material, not uncommonly large, freshly applied batches of organic matter like bark dust. They tend to appear and disappear equally quickly. They are really a curiosity more than anything to worry about. There seems to be a lot of this as I've had three Ask an Expert inquiries on this same topic this week. I include a link to a short discussion of slime molds from the PNW Disease Management Handbook.

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