USDA restricts certain items brought into the United States from foreign countries. Prohibited items can harbor foreign animal and plant pests and diseases that could seriously damage America's crops, livestock, pets, and the environment. Because of this threat, you are required to declare on a U.S. Customs form any meats, fruits, vegetables, plants, animals, and plant and animal products in your possession. This declaration must cover all items carried in your baggage and hand luggage. You will also be asked to indicate whether you have visited a farm or ranch outside the United States.
Travelers are often surprised to hear that a single piece of fruit or meat can cause serious damage.
And the extra cost for controlling agricultural pests and diseases ripples down from farmers to consumers in the form of higher food prices. Taking prohibited agricultural items from travelers helps ensure against outbreaks that could affect everyone. It may look luscious and wholesome, but fruit you bring into the United States from abroad could carry agricultural pests and diseases. In fact, it's possible that individual travelers carried in the infested fruit that brought the Medfly to California in 1979 and to Florida in 1997. Medfly infestations can cause billion-dollar losses to the citrus industry.