Cutting the root will in all likelihood not kill the tree; however, when you cut any tree root, it stimulates the cut end to grow even faster, so it's a pretty temporary solution at best. The surface roots around the tree indicate that the soil is so compacted that roots will not grow in it because it lacks sufficient air space. If the house foundation is a slab, I think you're right to be concerned about potential damage. The roots have entered an environment that is looser than the surrounding soil with lots of air and moisture. They will grow larger and larger and can in time crack the slab. A block foundation is also pretty vulnerable to root damage. A poured concrete foundation is the least vulnerable, but the first hair-like roots can still enter the tiniest crack and begin expanding. There are products which are sold as root barriers. Their installation involves a lot of digging and they are far from totally foolproof, but it might be worth checking with a tree or landscape company. It might be possible to cut the root and then install a barrier around the foundation side nearest the tree.

Is the drain perforated? If so, the maple will grow in to it. If not, it won't. Foundation drains are usually perforated. Downspout drains are usually not.....at least next to the house. Downspout drains should not be directly connected to the foundation drains.

No dead animals, no gas line nearby. I have had the root dug out, exposed to air for several weeks now. The smell has gone. The air bubbles are still there and the root remains wet even in dry weather. So I think sap is still coming from the root. I'm going to leave it alone until it all dries up. Then I think I'll fill it with sand. At least now I'm not afraid of having a health hazard in the backyard.

Tell me how to graft them! Been trying for 3 years to graft and all have failed. I am going to try air layer grafting next. It worked for my citrus after I failed at trying to graft them. Take spagum moss, the real stuff not tree moss most garden centers are selling the whole not ground up kind that you use to line hanging baskets with. Take a young one year old branch, not one that is older and the bark has gotten brown with age. Take a sharp knife and slice diagonally along the branch about half way thru the branch. dust with the root hormone powder in the cut. Important, put something plastic like a toothpick or a stirring stick you get from a Macdonalds in the cut to hold it open or it might grow back together. Next wrap with the moss and tie it in place with a thin pc of string. Also the moss needs to be Damp. you can try wetting it before wrapping or after. I did it later.. Anyway the next step is to put a piece of plastic over the whole thing. I prefer a white or black garbage bag that I rip the bottom corner off of and cut a hole in the tip so I can slide the pc down branch and over the moss. I then tie bottom side off first and then top. I don't use clear bag beause too much light promotes leaf not root growth and be careful of using black if it gets too hot it might cook the graft. try also cutting off tip of branch so it forces it not to continue putting energy into the branch growing longer. About once a week check bag to make sure moss is not drying out and add water until it runs out bottom. Hope fully after 2 to 3 months you will see roots in bag. If you get it to take, cut off below bag and take plastic off and plant, moss and all. This is best done in spring because plant is growing but doesn't hurt to try now just pick a branch that you don't mind losing if it doesn't work. Charles