Drought plagued states, including Wyoming, have been looking for sources of quality hay for livestock, however hay bales can be a vehicle for importing fire ants, a pest that can have negative impacts on both livestock and humans. Currently 14 states are under quarantine for these pests.

But the good news, according to Charles Brown, of the USDA's Animal and Plant Inspection Service is that hay from quarantined states can leave if it's not had contact with the ground. According to Brown, for bales that are stacked, restrictions are only placed on the bottom layer.  "Hay that is cut, baled, loaded, and shipped without storage can move without restriction. Baled hay and straw that is stored on an impervious surface such as asphalt, concrete, hard pan, that can move without restriction." Also hay thats been stored elevated can be transported to other states.

UCDavis.edu

States under quarantine for fire ants include most southeastern states, most of Texas, parts of California and New Mexico.