Could anyone help me identify what is going on with this silver maple. I'm located in Maryland just outside of Baltimore. This one specific tree always looked healthy until a few months ago. Currently the leaves and limbs on this tree still look healthy, but the roots have started to turn black, and crack. The wood where it's cracked looks as though it has almost dry rotted inside. I'm attaching some pictures. I'm a bit worried because this is a rather large tree and with the roots breaking like they are, I don't want it to become unstable and fall, possibly into the neighbors yard doing property damage.