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SethMMorton
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Orange sponge-like mold growing on mulch - what is it and is it harmful?

There is a mold that looks sponge-like that is growing in various spots on my mulch. It seems to appear very quickly (it seems like overnight but that's probably because I'm not observing daily), and I notice the following life cycle:

  1. The mold is a moderately rich orange color that looks neither dry nor moist.
  2. The mold seems to rise (like baking bread) and expand in diameter and turn a more pale orange (like in the first image below).
  3. The mold "pops open" and exposes black spores (like in the second image below).

I can poke the mold at steps #1 or #2 above to make it "pop" and have the black spore exposed.

The mulch was made from some trees that I had cut down on my property, one fir and one white birch.

I am wondering a) what is this mold and b) is it benign or could it be harmful to plants?

Mold in mid-stage life cycle Mold in end-stage life cycle

SethMMorton
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