How do you *start* a guild?

I keep planting trees and planting stuff around them at the same time. This seems stupid because seedlings probably need more water than the tree (and more superficial) and it still looks like barren soil around them. I keep wanting to mulch to conserve water, but then I worry about my seedlings coming up (and it's flippin hot and dry here). Do you all usually plant the guild and then the tree? I'm thinking this would have been the smart thing to do, but I didn't. Should I just mulch around the trees and hope stuff pops up through it?

I plant the tree and then the guild, not sure if thats right though. I mulch after planting, and when putting in plants around the tree, I avoid planting in the tree root zone, remove just enough mulch to put the plant in, and then transplant. Again, not sure if this is the right way but it's worked so far. I also let nature do a lot of the planting of my guilds in some cases. I figure that she knows better than I do about what would do best in a given piece of land.

Hmm... I was just planting seeds and not actual plants, but I have been planting in the root zone (n fixers and stuff).

I think that planting seeds in amongst the tree roots shouldn't be too damaging as long as you do it sparingly and/or are careful to not injure the roots. What seeds are you planting specifically? IMO most seeds will sprout through a light mulch. By light I mean not enough to fully cover the soil, but enough to cast shade. IF you're planting beans or other large seeds, in my experience, they will pop up through a complete covering of the soil with hay or straw.

things that i have planted in the root zone would be alfalfa and scallions.

I would think that the alfalfa seeds would come up under a light mulch, since they grow naturally in fields in that scenario. Not sure about the scallions though.

living mulches from seed are best started in the early spring, or in late winter for those with less snow. once it starts to get hot you have to mulch and then toss the seed into the mulch. then water well. just don't make the mulch too thick or with too coarse a material. 1-2 inches thick is good enough until the plants are established and shade the soil. if you see some small open spots its ok, toss some seed there.

to have the additional benefit of controlling weeds, you need to time it right so the seeds you plant grow before the weeds. once established weeds are a minimal threat.