The federal grazing fee for 2013 will be $1.35 per animal unit month for public lands administered by the Bureau of Land Management and $1.35 per head month for lands managed by the U.S. Forest Service.- The 2013 fee is the same as last year's.Treated as equivalent measures for fee purposes, the unit months are defined as the occupancy and use of public lands by one cow and her calf, one horse, or five sheep or goats for a month.- The newly calculated grazing fee, determined by a congressional formula and effective on March 1, applies to nearly 18,000 grazing …