The 297,000 mi2 (770,000 km2) of national forests and grasslands are managed by the United States Forest Service.[2] The safety of food produced and sold in the United States is ensured by the United States Food Safety and Inspection Service.[3] The Food Stamp Program works with the states to provide food to low-income people.[4] Advice for farmers and gardeners is provided by the United States Cooperative State Research, Education, and Extension Service.[5]