Hi, I may have really shot myself in the foot with this one. .. ok, here it goes... I have a growing bed in my garden that has been my holding/fattening bed for tree seedlings and potential bonsais. I planted various kinds of oaks, a larix seedling, elms, two tulip trees, American beeches, and a japanese maple in there between 2000 and 2005. I kept prunig them back, and the trunks have for the most part taken on nice sizes. However, I did not prune the roots in all those years, nor did I cut around the trees to restrict the roots from spreading. I garden in heavy clay, so the chances of finding lots of small feeder roots close to the trunks are very small. The problem I am facing is that this part of my garden will need to be redone sometime next year so the trees have to come out. I could delay work on that part of the yard until fall of next year, but not much longer. I am pretty sure the trees won't have enough feeder roots close enough to the trunk to dig them out in the spring and pot them or move them to a new location with a good chance of survival.

What options do I have at this point? I thought about air-layering the trees right above the current soil line, sacrificing the current roots but "harvesting" the trunks. It would give me good roots, but small ones that would take a couple more years to look convincing with the thicker trunks. Do you think I could slice through the roots with a spade right now (August) in a radius of about a foot around the trunks, cutting the roots and forcing the tree to produce new roots closer to the trunk? Would that work in time for next year? Or will it just kill the trees right away? Especially with the oaks (White, English, Red, Burr, Chestnut, Rock) I wonder if that just forces them to exclusively rely on their tap root... Does anyone have experience with this? Thanks for your ideas and input.