Question
We are putting a purchase offer on a home with a very large Banyan tree relatively close to the home.  It is huge...  Our concern is what type of damage to the sewer pipes this is creating.  It is an older home with no foundation and no visible showing of any damage to the floors/patio ect.I assume the tree is done "Growing" but is very overgrown, some branches hanging over the roof, lots of vines growing within it. We have great concerns of what we are not being told about this issue and the damage this may be causing.. Also a concern is whether we could be held responsible for any damage to the neighbors property in the future.  It is a shame to destroy such a beautiful tree, which would be quite costly but we do not want to buy something that is going to cause us a lot of problems dollar wise in the future. Any comments to this issue is appreciated.  We don't even know who in the community to contact for a honest answer to whether this has been a previous problem or not.  This tree is located in south west Florida.

Answer
Well this tree is invasive and will grow about 100 feet tall and at least that wide. It needs a lot of space. Close to a house is the wrong place. Its roots are considered to be a problem with septic tanks and lines. Older sewer lines usually have cracks and the roots will enter the lines causing blockage . Newer sewer lines are sealed better and usually are not a problem for roots. Patios and driveways sidewalks are damaged by their roots.

I would say have the owner take the tree down before you buy or close. When it is cut the stumps and roots stumps should be treated with a herbicide called Garlon (triclopyr) this should kill the root system. Or otherwise the tree will sprout new growth.

It is actually on the list or prohibited plants in Florida and banned in Miami. Might check with the Florida Extension service in your area.

http://miami-dade.ifas.ufl.edu/old/programs/urbanhort/publications/PDF/Miami-Dad