Updated

At a time when security is being intensified at airports, power plants and stadiums, agriculture officials say farms and the food supply remain among the nation's most exposed targets.

And agroterrorism — attacks on the food supply or turning agricultural materials into weapons — is nearly impossible to guard against, they warn.

Fertilizers can be used to produce powerful bombs, pesticides can become chemical weapons and just a tiny amount of deadly bacteria can taint the food supply for thousands of people.

``Agriculture is vulnerable,'' said University of Georgia agriculture dean Gale Buchanan, part of an association of academics that has formed a task force on the issue. ``There's no way you can put guards around fields or animals.''