Usda Aerial Imagery — Download |link|

Accessing USDA aerial imagery allows you to track historical land-use changes, perform environmental assessments, and manage agricultural property with high precision. The is the primary repository for this data, housing more than 10 million images dating back to 1955. Primary Sources for USDA Aerial Imagery Downloads

Depending on whether you need current or historical data, there are several federal portals available for free download: usda aerial imagery download