Question
Pondorosa Pine root system
I have a similiar question for you regarding a ponderosa pine and roots lifting the asphalt.
Our cabin is located in Pinecrest, CA approx 6,000 ft elevation.
The family that built the home had second thoughts about removing the large tree.  It is in front of one double garage door (about 12 feet away)The driveway runs right up to the edge of the trunk.  The living area is above the garage.  The tree is about 50/60 ft high? and about 5 or 6 ft in diameter.
One root is growing under the driveway and causing the asphalt to rise going into the garage door opening that we can use.  There is a noticable crack following the root.  Can we cut the one root near the trunk that is heading that way without harming the tree or endangering our structure?  I am not sure if cutting the root would weaken the tree against snow or heavy winds.  I would be happy to take a picture when we visit this weekend.  Thanks for your time.  Marianne


Answer
Pine trees have a tap root that is the major source of water etc for the tree so cutting the root that is going under the drive will not damage the tree. You can cut up too about 30% of the roots of a tree without causing serious damage to the structure of the tree. Cutting this one roots will not make any difference to the tree as far as weakening it or causing health problems to the tree.