Subsistence farming is the kind of farming done by farmers who have small plots, or little water, or otherwise grow enough only for themselves. Literally, subsistence agriculture means no extra food is produced to sell or trade. This means farming doesn't give them money to buy things. However, today most subsistence farmers also do trade to some degree. From time to time they may need money to buy essential things to keep going.
- Tony Waters 2007. The persistence of subsistence agriculture: life beneath the level of the marketplace. Lanham, MD: Lexington Books.