I've been hunting an old High School built in the teens or early 1920's . It has a park like setting on the front and side lawn with 100 year old trees or older. Perfect place to use a small coil,which I don't have yet and the trashy park setting. Heres my problem , using the stock coil I have had a reading at least 3 times with a Co of 45 or 47 at a depth of 6 or 7 inches. When I get down to the root 5 to 6" in diameter and using my X1 probe I still get a co reading of 45 or 47 and its as solid as can be with my probe. The probe keep sounding off as I would dig but I can't find the target. So I gave up on the first 2 like that. On the third time it happened I put the probe on the exposed root itself and I would get a solid Co 45 rubbing my probe on the root. these roots are 5 or 6 thick . They will have the most solid sound I've ever heard. I tried this on 1 of the other tree roots and the same solid hit . Can tree roots give off a false reading ? If so, Why?