fruit guildes around young fruit trees

Hi,
We are planning to create some fruit guildes around young fruit trees we just planted (1 to 3 years old). We will be following the schema proposed by Toby Hemenway in his Gaia’s Garden book and replicated by many permaculturists (example:

http://kitsaptilth.org/wp-content/uploads/2012/09/fruit-tree-guild2.jpg)
We have two questions:

1) Shall we already build the guild considering the drip line at maturity or should we create it more proportional to the current size of the tree?

2) I am thinking to surround the guild area around the tree with stones and/or wooden boards to minimize stepping and mark the “cultivated” area (it is a public area) but how to best do this?
We still need to reach the tree for pruning (yes we are considering the no pruning option but that is another post ☺) and harvesting (though production will be minimal the first years). Also let’s assume the answer to point one comes out with a quite large guild (2.5 meters around the trunk?) this will force us stepping in for planting and harvesting the guild plants (eg. beans, fennel). Shall we put boards or flat stones inside the guild for stepping? Do you have any design suggestion?

Thanks a lot.

I would put long term perennials at the mature dripline and annuals at the current dripline (e.g. dakion radish for aerating the soil and accumulating nutrients) just make sure that they are not competing for water/etc.

I wouldn't put anything at the current area i estimate root growth is at. i would keep that area as free from weeds and grass as possible. the tree is going to need good care it's first year or two at least. the area i would estimate as outside the current root zone is where i would put beans and nitrogen fixers. then maybe next year, shallow-rooted anything you want, or more beans. further out can go your deeper rooted anything you want. bulb-type plants are good for underneath your fruit trees, as they have very little root systems.

i have young 3-4 year old apple trees that are showing signs of fungus issues - spotty leaves and all. I thought a guild would be the answer but sounds like i would be acting too soon. Any thoughts?