lasagna gardening

Hi all, I am looking for some advice. I am planting fruit tree guilds at my local community center. I have used the layering of cardboard as the base for previous lasagna gardens and have recently decided its not environmentally sound to use cardboard or paper. The City wants to till the area first and we are planting established trees as the city would like to have an immediate example of food guilds. Can anyone offer advice as to how to lasagna the area around the fruit tree (we have compost, top soil, mulch and straw bales), and how to plant the fruit tree so that the area around the tree does not end up too high up the trunk of the tree? I am thinking of using a biodegradable landscape fabric then layering with straw, compost, and top soil. For the fruit tree I was thinking of planting it halfway in the soil then building the remaining up to meet the bed, thoughts?

So I don't get it, cardboard is not sustainable but landscape fabric is? Is that what I just read?

cardboard usually has a glue that keeps it together and does not allow for much air or water to get through. There are biodegradable landscape fabrics that can suppress the weeds, but don't inhibit air or water.