Adverse Possession:
“Adverse possession is a doctrine under which a person in possession of land owned by someone else may acquire valid title to it, so long as certain common law requirements are met, and the adverse possessor is in possession for a sufficient period of time, as defined by a statute of limitations.”
This crap was used to acquire land owned by my grandparents in Texas. The squatter used the land (old family farm) for grazing for some years and then claimed ownership. Fortunately, one of the heirs was an attorney and was able to retain the mineral rights for the rest of us. We didn’t care about the grazing but the land is on the NE edge of Eagle Ford. ;>)
Minerals are not automatically titled with surface.
If you allow someone to ‘use’ your land for a undetermined time for undetermined purposes, there are certain conditions where Adverse Possession may apply. Although, adverse possession is a rarity and is relatively easy to defend from such claim. As with most things, an ounce of prevention is worth a pound of cure.