The owner or owners of any land or lands in this commonwealth who shall maintain upon said land or lands sprout forest or timber trees, in number not less than three hundred to the acre, shall be entitled to and receive the rebate of taxes as provided in section one; said period of exemption to be counted from the time the said land or lands shall have been so maintained with sprout forest or timber trees, or from the time that said sprout forest or timber trees may have been destroyed by fire.
72 P.S. § 5584