So we recently got chickens and when they were first in their run there was plenty of grass, now over time it is just dirt? Is that ok? Or should I put something down? If so what?
My chickens ate all the grass in their runs long ago. Iowa was in a drought all summer, so I didn't have to do anything and they were happy to dig dust baths in the dirt. However, in a normal year, I throw wood shavings into the run so they aren't walking around in mud.
Optimally you want some form of litter in the run to allow for poop clean up/comspoting and to manage mud. Most popular choices are probably deep litter and sand, though what works best for you will depend on your location, your flock density, your run set up, run management, etc. Sand tends to work well if your run stays dry most of the time and you're able to regularly scoop poop. Deep litter tends to work better if rain/mud is an issue.