How large should tree guild be?

In the book, Edible Landscaping, Michael Judd sheet mulches 8 X 8 squares before he plants his fruit trees. He has these large squares throughout pasture wherever a tree will be planted. I have already planted my trees but have not sheet mulched around them yet. I can see why you would want to make your guild ring the size of the full-grown tree from the beginning and get all those plants in there to protect the tree from insects. It is also easier than gradually expanding your ring every few years and having to add plants in my opinion. Is 8 X 8 overkill or is this the typical size of dripline of a full grown medium-size fruit tree?

Thanks,
Beth
Idaho

Hey Beth -
There really isn't any metric for a guild, it's more of the combination of things you plant. If you think about an 8X8 with a tree in the middle, it's only 4' on any given side. The dripline of a mature fruit tree will go way beyond that point. When considering the "what" to plant around your tree, it's less about keeping bugs away then it is about plants that will partner well with each other and feed the soil. My orchard was in place before I put in a guild, so to speak and today, almost the entire orchard is planted with beneficial plants, herbs, perennials, other fruits bushes and brambles as well as annual veggies. There literally isn't any barren space. This type of "forestation" makes for a beautiful and healthy garden not to mention that we don't have a bug/pest problem.