Land is leverage-able, at low interest rates (think mortagage at 1-2%). So, if he believes that the value of a certain area will increase by 50-100% over the n

Land is leverage-able, at low interest rates (think mortagage at 1-2%). So, if he believes that the value of a certain area will increase by 50-100% over the next decade, and he can borrow against it for cheap, it actually wouldn't be advantageous to sell it. If land taxes would be higher, he would probably sell it.