Act shall be subject to 4 cumulative years of a reduction in benefits under this section as described in this subparagraph. (bb) Hay and forage crops During each crop year of planting, as determined by the Secretary, native sod acreage that has been tilled for the production of a hay or forage crop after the date of enactment of the American Prairie Conservation Act shall be subject to 4 cumulative years of a reduction in benefits under this section as described in this subparagraph.