Columbia subject headings:
Agriculture--United States.
Climatic changes--United States.
Crops and climate--United States.
Meteorology, Agricultural--United States.
Harvard subject headings:
Agriculture--United States
Climatic changes--United States
Crops and climate--United States.
Meteorology, Agricultural--United States.
Princeton subject headings:
Agriculture--United States.
Climatic changes--United States.
Crops and climate--United States.
Meteorology, Agricultural--United States.