Great!Zone 5 for me
Dappled willow grows incredibly fast and can be planted in poorly draining areas.
Privet hedge grows fast and you can prune the lower branches to make it a better canopy for the chickens to get under.
I also have a PeeGee hydrangea. They grow fast and the chickens don't destroy the leaves on them.
I will also be using @21hens-incharge 's idea of putting chicken shelters in among the juvenile plantings. I have unlimited access to 55-gallon barrels from work. I will be cutting the tops and bottoms off of the barrels then cutting them in half the long way to make two curved "chicken caves" that are open on both ends so they can run under them whenever they want. They will be black so hopefully will blend in behind the plantings better than bright white or blue.