Starting next spring I will be establishing plantings of briars, grapes, osage orange, and possibly Russian and Autumn olives to provide cover from hawks and break line of sight from foxes. It will take years to get some cover patches up to working density. Existing cover patches in the form of multi-floral roses, wild rasberries, sweet sumac, golden rod and some sort of densely growing milkweed have worked great so far but patch locations not where bulk of my pasture is accessible for foraging with short retreat time back to cover. I want my birds to stay on my land as much as possible. Now that heavy hawk season passed, birds still using cover for a completely different reason, cover from wind. They stand among existing cover plants but always where sunlight can strike directly. A recent trip to North Carolina exposed me to a different way to setup grape arbors. They were trelised (sp?) to form an upside down box. The wiring itself provides some structural protection. What I do not know is what minimum diameter of cover patches should be and how far apart they can be and yet provide good protection. Chickens are not as fast as hawks but they can beat former to cover if enough lead time. I am probably going to use chickens present associations with cover to estimate distances between cover patches.