I would like to plant a small tree or shrub inside my chicken run. It is a small run. I have 9 hens but I am trying to 2 give away- said they would take them months ago...but havent yet! There is little shade for several hours/day plus there are hawks visiting lately and i think the girls need cover. Additionally it would be a lovely tree over time. My yard is small for my house and keeping the yard as pretty as I can is important to me. I attached a photo of the tree i was thinking of. In the ground it will be about 5" with low branches only a few inches from the ground- so it will be months before they can "use it". I figure I would have to contain the tree in 1/4 inch hardware cloth for a few months to protect the roots and leaves. By that time it will be fall. Right now I have our old xmas tree as a stand in for shade and cover. The local sparrows love the dead tree but the hens seem to have outgrown it - only one can fit under it at a time. it is a temporary fix. I also built a sort of teepee which 1-2 can use at a time.
We have a tree in our run thats smaller. Its protected using chicken wire to keep them out. Like yours, it'll be staying there for shade. However, the tree may also make it easier for them to get out of your yard if its close enough to the fence.
My chickens like roosting in our japanese maple but its about 12-15 feet tall and 20 years old. If the birds werent confined to the pen with the tree it should be fine. If they are confined with it, they might damage it, maybe not. My friend has a few small trees in his pen and they dont bother them, but he lets them free range some each day. You could always build a shade structure for trumpet vines or something of the sort to grow up the sides, just a thought. Best of luck to ya!
I would plant the tree outside the run where it will still give them shade during the hottest time of the day.
For inside that run, I'd try shrubs that are less expensive! You may find that covering your run, at least with bird netting, will keep your flock a lot safer, and plantings that won't outgrow the space will be better anyway. Right outside the run, trees and shrubs will provide shad and look great too. How about viburnums? Mary