Industry Idaho trumps Pennsylvania By DairyHerd Staff January 17, 2011 | 7:07 pm EST Comments Print Idaho has once again secured its position as the fourth-largest milk-producing state, relegating Pennsylvania to fifth place in the lineup of top dairy states. In 2008, total milk output in Idaho topped that produced in Pennsylvania in all 12 months of the year. Idaho has not yet surpassed New York. Total milk production in Idaho fell short of New York output during eight months of the year. It only topped New York in July, August, September and October.