james, Roughly where are you? Zone 10 should not have cold enough winter temps to worry about damaging the root system. As for what you did, I don't like the tar ideal at all. The tree will have to grow new roots, and those start from the pruned end of of the cut roots. Putting tar on these could very well interfer with that process, not to mention hold moisture that would favor infection with various bacteria and fungi from the soil. No, I don't like it AT ALL. Beyond that, some shading from direct sun would likely be very beneficial. Would certainly reduce water stress while new roots generate. Keeping the soil cool and moist but not wet would be beneficial as Im sure you know. Judging from the pic, that probable won't be an issue. As for Acer gresium, they actually seem to be more forgiving to girdling. I have seen where trees were kept in those tree band pots for too long and been potted up. Those roots had actually grafted on top of the original flare, and the tree was non the worse for the experience. I assume since the bark is so thin and sheds annually, that this facilitates the grafting. If you look online at mature Paperbarks, I don't believe you will find many with indications of bark inclusions at branch points. I know I don't remember seeing any despite some tight angles. That also would seem to suggest that they self graft freely. Arktrees

I think you have done the right thing and you may well be OK. Here is what I know, or think I know about girdling roots and maples. First, they can be a big problem and are often fatal. That said, every case where I could determine that a girdling root was killing a tree, the girdling root was around the trunk at or above the root flare. If one root circles another root lower down I am not sure it is a problem, but frankly I have never dug up any dead maple to determine if anything like that killed it. But my theory/idea is that any root below the root flare of a trunk that may be locked up with other roots will generally graft with them and not cause a problem. But a root that crosses the trunk of a tree--at or above the root flare--will not, by itself, develop a graft and defeat the strangling. This may be because the kinds of cells above the root flare are different from what is in a root. Or at least there is some incompatability that prevents grafting, it seems. So, if you keep an eye on these trees as they grow, and if as the roots grow and the trunk gets bigger and bigger, you see some root that seems to be at that time close to the trunk at or above the root flare, you can cut it then. Of course if you could do a little more of what you have been doing and discover any more roots that could be a problem later, cut them. Of course, if the root flare is below the soil, remove the soil to expose it. No, definately don't lose any sleep--you are on top of the problem now! Girdling roots seem to kill a number of kinds of trees. Hickories like maples seem susceptible. But my Norway spruce and white pines in my forest stands often have roots crossing and or partially circling the trunks above the root flares, and these trees graft to them and grow right over them and it seems not to hurt the trees at all. --Spruce

Great input! I appreciate all of it. I'm in the middle of hand surgery, as luck would have it, so I truly can't dig far, but I brushed all the leaf litter away (and there was a fair amount this time of year) and went down a little further with my hands. I think I found root flare. See what you think from the pictures. That leads me to believe the tree might be planted an inch or so below grade -- although this is a slope and the pictures are on the downhill side so the uphill side may be more buried. I failed to answer someone's question about its apparent health during the summer. It has grown like a weed and has leafed out beautifully each summer. The canopy was skimpy the year it was planted, but about a month or so after leafing out last summer it suddenly had a mature canopy. Here are the pix:

Great tutorial Nell, I'm going to try this with some of my shrubs. This method really works with perennial Asters (Michaelmas Daisies). Great way if sharing with someone through the mail :o). I usually do this in march, dig the clump, discard the center, cut the roots into small pieces that have growth buds on and either replant 3 or 4 pieces back in the hole, in 4" pots (garden club plant sale) or wash them off put them in ziplock baggies in a bit of damp paper towel and send off in the mail. I should think this should work with other plants as well. You've got rid of the soil, so there goes the weight, when the root cuttings arrive they can be potted up and grown on or planted out. This is how my daisies came from England as no soil is allowed into the country. The only other way I could have got them would have had them rooted in rock wool, this was so much simpler. Annette