; and (iv) by adding at the end the following: (B) those activities and the activities described in paragraph (3), not more than 1/3 of the acres covered by the contract may be harvested during any year; ; (D) in subparagraph (B) of paragraph (2) (as so redesignated), in the matter preceding clause (i), by striking grazing, the first place it appears and inserting grazing outside the normal grazing period described in paragraph (4), ; (E) by inserting after paragraph (2) (as so redesignated) the following: (3) mechanical harvesting of vegetative cover, without any restriction on the use of the vegetative cover harvested (except harvesting the vegetative cover for seed), subject to the conditions that— (A) the harvesting may not occur more frequently than once every 3 years; and (B) the annual rental rate for the acres harvested during a year shall be reduced by 25 percent; (4) grazing during the applicable normal grazing period determined under subclause (I) of section 1501(c)(3)(D)(i) of the Agricultural Act of 2014 ( 7 U.S.C. 9081(c)(3)(D)(i) ), without any restriction on grazing during the primary nesting period, subject to the conditions that— (A) the grazing shall be at 25 percent of the normal carrying capacity determined under that subclause; and (B) the annual rental rate for the acres harvested during a year shall be reduced by 25 percent; ; and (F) in subparagraph (C) of paragraph (6) (as so redesignated), by striking (3) and inserting (2)