Should i be worried about this? crusty flaky skin.

[yanischickens]

I have checked my entire flock for mites and found indications of them on two of my hens. However, this one in particular looks perfectly healthy besides the flaky spot on the back missing feathers.

 

[yanischickens]

We treated all of the chickens and their coop with diatomaceous earth and have followed it up with first saturday lime. I am at a loss at what this could be :/

 

[Ursuline Chick]

I am not an expert, however, there are mites that will cause feather loss. My understanding is that they can be treated with Permethrin. I also understand DE doesn't work well and may cause respiratory problems for both your flock and for people around your flock. Permethrin comes in spray, cream, etc. We use Permethrin for our flock and find it works really well.
Welcome from New Orleans. I hope this information helps and I am sorry to meet under a problem situation. Good luck, I hope you are able to resolve your chickens lice problems.
You will have to treat your flock and clean and treat their living quarters, focus on crease and cracks.