Your question brought back a long ago memory. Walking through the extensive vineyard of a master New York State vinter he told me that established grape vines send roots 100' downward into the soil. Cannot say that this is true or not. I just always remembered his claim. Two thoughts as I read your question: 1. The new concrete will leach lime for many years raising the soil pH beyond the comfort level of growing any plant, including grapes. This means working with and amending the soil for about the first ten years with acidic compost or commercial products for this purpose. 2. Your plan of a seating area works. Check with some local growers of trees to see if you can find a very large, heavy duty plastic pot, remove the bottom, sink it in the hole and plant. This would be the ideal solution, forcing the root system down. Second choice would be lining the planting hole with 5 mil plastic sheeting. And, grapes grow quickly. It would be an easy job to kill off one that has grown out-of-bounds and replant with a new one.

I imagine you'd have the same type of root problems that occur with sewer and drain pipes. Probably depends on the crop and how often the field is plowed. In landscape irrigation, we used a tube that had tiny holes drilled in it with a laser. Those holes did get clogged from mineral build-up with time, but they were quite small. Tim

You have gotten a lot of advice here, some of which may seem a bit contradictory, so I am not surprized that you don't have a clear idea of what to do. First, let me say that as I have read this thread I have not jumped in because what I have seen here has generally been good advice. But I see now that you need a referee or something, so I will try to help. One of the problems is that all trees are a little different. Not only is the degree of root "congestion" in the pot different, but different kinds of trees respond differently to different treatments. But I can't see--and feel, etc.--the roots you are dealing with, and I am not familiar with all the different species of trees and how they may react to different treatments. But let me give some general advice that will help you. First, if you do any of the things recommended, it will be either good or OK. Slitting the rootball in thirds will keep any of the encircling roots from strangling some of the roots later. But undergropund roots generally don't strangle the tree--roots generally graft over themselves. The real danger is a root that encircles the base of the trunk (girdling root). These must be removed. But better than slitting the root ball is as much as possible to "tease out" some of the encircling roots so they can be extended a bit. But often the root ball is so tight with the roots crossing each other, both in and then outside, that this is virtually impossible. In this case slitting the ball in three places is about all you can do. If you can tease out/unwind some of the roots (and you can both do this and cut some larger/longer encircling roots) you will need a big hole to allow them to spread out a bit. But some of the roots you are able to tease out/unwind may be very, very long. In that case it may be beST to shorten them a bit, or a lot, because if you don't, they will still encircle the root system or make a tangle. But if that happens, it is not really fatal. Sometimes with some kinds of trees in pots the root ball just seems like a dense fibrous mass. It is hard to find individual roots to tease out/unwind. In that case three slits and then some roughing up of the root mass to loosen it a bit is about all you can do. If you do any of the things recommended here, you will be doing more than most people do when they plant these root bound trees. Have confidence and go ahead and do the best you can--use your common sense. A lot of this will be intuitive as you start working with these root balls. Just see what you can do to undo some of the tangle, one way or the other. But one warning--these root bound trees will need more watering for maybe up to three years than a tree not so root bound. The roots will need time to get into the native soil--water that gets to the root mass that was originally in the pot will not last more than a day or two in hot weather. The more roots you can unwind/tease out and get into the native soil, the more drought resistance the tree will have. --Spruce

IMHO.. they are useless ... especially as noted ... they are a preventative.. not a remedy ... dad had to have his professionally bored out.. with camera verification .. and has to rotorooter his 2 or 3 times per year ... the machine to do it himself is about 1/2 the cost of one visit from the pro service ... he is dealing with 2 maples ... the neighbor has a sycamore... and his pipe to the sewer.. had to be dug up .. and on a 4 or 6 inch pipe.. i wasnt there.. the 60 year old tree root.. had filled in.. all but one half inch ... the root was 4 or 6 inches ... as you can see .. some copper solution wasnt going to get rid of the root ... now.. i have no opinion.. in regard to whether.. if you had it thoroughly cleaned out ... and inspected by camera ... that the copper solution MIGHT work as claimed as a preventative ... its a few bucks a few times a year ... but unless you bring back the camera .. its all about faith ... i think dads idea of just rooting it is probably the only definitive solution ... or the neighbors.. who replaces the old tubular ceramic tiles/pipe with hermetically sealed pvc ... this is going to cost you money.. there is no way around it ... IMHO ... and i have no clue how to prove its a neighbors tree.. two houses away from you ... doubt that is going to work ken