From 5½ decades of dealing with tree roots, I concluded that there were certainly some coins that ended up positioned below a root, but that was generally due to a younger root-sprout growing over the already lost coin. I enjoy finding the older coins and tokens and such, and that means fining the older-use parks, schools, picnic groves and other areas that were already treed-up locations. I mean to lose coins back in those earlier days under trees, they already had to be there.
Thus, in most cases and depending upon the types of tress and their root growth, most of the trees and roots were there when folks made use of their shade. Coins, tokens and other pocket-carry items got lost and those were on or close to the surface. Coins and such do not sink, but they can end up being displaced or covered up and, in time, will end up closer to he tree roots. One of the causes for that, remember, is the tree growth also beings about root growth, and roots do not only grow or enlarge on the bottom site.
They grow all around, and a smaller 1" to 2" diameter tree root at the time an old coin was lost might measure 6" in diameter today ... or more with a much older tree. So let's 'average' that root at 1½" in diameter, and today the root is 6" in diameter, that means the outer edge of the root is now 2¼" wider on either side, and on the bottom and now 2¼" closer to the ground level ... if the ground level was unchanged. Due to the root growth it can relocate a coin that was under it before so it is now deeper, but it can also push a coin closer to the surface if it was on top of or over the root.
The bigger challenge is trying to find the more difficult coins, and those are the ones that were lost near the edge of or nearby side of a root. As that grew it could leave a coin or token in more of a 'canted' or 'on-edge' position. I know for a fact that there are times when the Hobbyist has tried to isolate an 'on-edge' or canted coin and tried to retrieve it, but the position wasn't well pinpointed. Here we can acknowledge a good benefit of using a Pinpointer which we didn't use to have. Anyway, the angled coin was difficult to find and the searcher presumed it must be deeper, as if maybe under a root. More excavation got them deeper, and in doing so the edged / angled coin ends up laying relatively 'flat' near the bottom of the hole and they now find it. There now, but it was positioned a bit shallower before the extra diffing.
I have found coins under roots, so I am not arguing that point. And with some ground build-up, fro =m cut grass and fallen leaves, that can add a little more to a lost coin's depth. But in all this time I have never needed an 18" hole to recover a coin-sized target associated with any tree covered environment.
My real problem is finding an OLD tree-filled park or similar location that hasn't ben grossly altered since the early era of those trees being used. Here in Vale, Oregon I found a lot of good stuff back in '74 and '75. I moved here almost 5 years ago, but sometime back around '78 to '83, from what I was told, they took out most of the big old trees, re-contoured the park and added a sports field and other things. The park was grossly altered and today roughly 40 years later, most of the trees are long gone as well, as most of the old dirt which includes all the old coins and ????
Need to drive around more dated locations in search of older trees and cross my fingers.
Monte
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