Q. How do I stop the roots of ailanthus from getting into the plumbing??
The ailanthus is in an inner courtyard. Its roots go under the house and get into the plumbing and cause damage and inconvenience. How can the roots in the areas between the house walls be stopped without killing the whole tree.??? Would copper pennies deter the roots??. A spray?? Copper sulphate no good as it can't be flushed out .
Unless you are able to build a physical and impermeable barrier to the root system of the tree, which undoubtedly is a huge and expensive project, there is no way to stop a tree from extending its roots in search of water and nutrition. If the tree is damaging and destabilizing your house, you should consider removing it. This tree in particular will otherwise continue to spread and damage your home.
Ailanthus is well known as an invasive tree with a very, fast growing and wide-spreading root system. It attempts to reproduce and spread by sending out root growth and will endeavor to re-sprout even if cut down. You will need professional help from a certified arborist to kill and remove this tree. More information on the invasive properties of Ailanthus altissima from Penn State University can be found here. You can find a certified arborist in your area by referring to the International Society of Arboriculture website.
Courtesy of NYBG Plant Information Service