I had very much wanted to free range when I first got chickens, but nixed that due to an extremely high predator load. So, we fenced an 80X80 area, covered it with aerial netting and ran electric fencing around it. Even so, we've had losses as wily predators found gaps in the netting, an un-electrified door gap, etc. Everything does like chicken.
In being forced to keep them confined to one yard, I've learned that if you put straw/mulch/autumn leaves in on a regular basis, over the years, it can grow decent forage.
Here is a picture I took last year of part of the yard. This spring, the forage was even more dense an varied. DH even had to get out the weed whacker to clear some open areas. When I first started 6 years ago, the entire thing was bare dirt, not so much as a weed.
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