White powdery substance 2” to 10” deep in my soil.

Asked July 28, 2019, 9:46 PM EDT

In one of my wood planters I found this white powdery substance about two inches under the hemlock mulch. It can be found down to about 10” deep and settles in a thick layer in very, very dry soil. I have not seen this anywhere else in my garden (and I have a lot of garden space). It doesn’t look mycelium. It seems to like to collect around the roots of plants but it is scattered through-out the garden bed, roots or not.

Multnomah County Oregon soil

1 Response

I'm responding on the fly here, but yes, I'd say mycelial threads.

It's very dry right now, so powdery would about describe it.