Have you tried a solid-bottom feeder like this, mounted at "back height" on the wall: http://www.mypetchicken.com/Chicken_Supplies-Solid_Bottom_Feeder_two_sizes_-P600.aspx ?
I'm ordering one this week for my chicken tractor.
You can find it more inexpensively at jefferslivestock.com -- just search for "solid bottom rabbit feeder".
I'm ordering one this week for my chicken tractor.
You can find it more inexpensively at jefferslivestock.com -- just search for "solid bottom rabbit feeder".