I don't have any insight. I came here to ask the same question. I don't think spores would come off mine but it looks pretty early on.

This just appeared today. We have had several days of rain though so today may have just been the first time I noticed it. After looking around it was all over the soil as well. The sun was out very bright all day today though and it dried whatever this is up enough that it fell off of the plants. I knocked off what was left and scraped it off of the dirt then applied a home made remedy that some one recommended. We will see what happens. The plants still look very healthy so I am hopeful.

I responded on your other thread.

Slime mold, one of the many. Not a problem.

I saw that jean001a. Thank you