All surface land which has, since the fifth day of June, one thousand nine hundred and thirteen, been classified and set apart as auxiliary forest reserves, in the manner provided by law, or which may hereafter be so classified, shall, so long as the same remains so classified, be rated in value, for the purpose of taxation, not in excess of one dollar ($1.00) per acre, and shall continue to be so rated so long as the said land remains within the class designated as auxiliary forest reserves: Provided, however, That if the said surface land be underlaid with coal, iron ore, oil, gas, or other valuable minerals, said minerals may be separately assessed. The elected and appointed assessors in the several boroughs, townships and districts in which such lands are situate shall assess such lands in the manner now or hereafter provided for the assessment of real estate for purposes of taxation, as if they had not been set apart as auxiliary forest reserves, and shall make their return to the county commissioners in like manner as is now or hereafter may be provided by law, subject to exception, appeal, and final adjustment.

Upon receipt of assessment returns from the various assessors, the county commissioners, or board for the assessment and revision of taxes, shall reduce, in their records, to a sum not in excess of one dollar ($1.00) per acre, the assessment on all those lands which shall have been placed in the class known as auxiliary forest reserves, in accordance with certificates filed with them by the Department of Forests and Waters,¹ and the original assessment returns made by said assessors shall be preserved.