This is my first post so we'll see how it goes... I have been very excited about permaculture over the last several months, it's been a real life changing discovery, but, maybe because i my development has only followed what is directly applicable to me, I've been stuck on guild design. I am aware of the complimentary species of plants in both the Apple guild and the Walnut guild, and I am very much aware (through my own experimentation) of the Three Sisters. But what i lack right now is the method of determining what plant goes with what tree. For example, i understand that the apple tree draws moisture and nutrients from the surface, so grass suppressing bulbs are necissary around the trunk and dripline of the tree. I am also aware that muching is good around an apple to keep moisture to the roots, and as always insectaries and nitrogen fixers are vital. With the walnut, i understand that everything has to be relatively immune to the effects of jugulone, as most berry bushes are and nightshades seem to be. But when it comes to developing my own guild designs around such trees as the persimmon, almond, chestnut, and local natives, i'm sort of lost as for how to go about finding compatible/symbiotic species. Can anyone help me with a list of guilds that work, or provide me a method by which to create my own sound guilds?