[Arid_gardener] Invasive Tree Roots

[Mark Di Lucido]

I have several beautiful, mature trees in my front yard.  At least one of
them has infiltrated my sewer line as evidenced by rootlets on the business
end of my favorite plumber's drain snake.  I don't want to remove any of the
trees but will consider this if it means I can once again use my kithcen and
bath without worry.  My question is: Is there a way to match the tree
rootlets (I saved them in a baggie) to leaves (above ground tissue) via some
kind of testing so that I may determine which is the offending tree?   My
hope is that by identifying the infiltrator I can selectively remove it
while not disturbing the others.  Here are the particulars: The location is
Prescott AZ; the tree species are Quercus emoryi, Quercus arizonica, Ulmus
pumila, and Morus microphylla.  All the trees are very large, up to 60'
tall, and all canopy drip lines are well within range of the sewer line.
The sewer line is approximately 4.5' deep.  I deeply irrigate the root zone
area during summer dry periods, the rest of the year is precipitation only.
I also have subsurface roof drain lines that the same roots have invaded.
Thanks in advance for any help.

Mark D.