Is there any way to identify tree roots? The other day my sewer line was plugged so I called my local plumber to clean it out. When he pulled the mechanical drain out there was a big mass of tree roots. My sewer line runs under my driveway (I cant imagine a worse location). On one side is a pine tree, on the other is a maple tree. The sewer line runs pretty much between the middle of these two trees. I would like to identify the roots so I can tell which tree is the culprit.