Mysterious mold/fungus showed up in our run overnight

[Rhyara]

This was all along the the side of the part of the run that gets rain. Upon further inspection there were some small clumps of it growing by our boot cleaner too, making me think it's related to wet chicken poop.
Anyone know what this is and if it's dangerous?
I scooped out all I could see into a bucket and took it away from their run.

 

[Rhyara]

Just recalled we tried to pick up some kalmbach crumbles from our local feed store last weekend, but when we poured it into our feeder there was a mold spot in the middle.
I took out the feeder, dumped the feed in the garbage, and deep cleaned the feeder before going back to the store and getting a different kind of feed.

I'm guessing a couple of rogue crumbles escaped escaped and that mold started thriving adter the rain. I have no idea what kind it is, but hopefully I've been able to remove it all. I feel better knowing what the probable source was.

 

[Eggcessive]

Mold can form in feed bags especially if they have been left in a hot vehicle where the feed could sweat in the plastic bag. Also if you are scooping the feed from a garbage can or container, and even a couple of drops of rain get inside they will cause mold to grow. It happens almost overnight in warm weather, and scratch grains will easily mold in summer weather. Spilled feed on wet ground or under feed pans will mold overnight. Mold can be toxic to chickens if enough is consumed.