Agriculture is a major industry in the Plains, Midwest, South and California, USDA data show, and the obverse holds too – in many congressional districts, farming and ranching is a minor economic factor. USDA’s 2012 Census of Agriculture says there are fewer than 5,000 farms in 57 percent of the 435 congressional districts. In 62 percent of congressional districts, the market value of agricultural products sold was less than $500 million; in 77 percent of them, sales were less than $1 billion.
By contrast, the No 1 agricultural district, the 3rd House District of Nebraska, covering the western three-quarters of the Cornhusker state, had 35,580 farms and $17.7 billion in sales in 2012, according to USDA. Six other districts in the upper Midwest and northern Plains topped $10 billion in sales and all had more than 30,000 farms apiece.
Mechanization and consolidation have reduced the U.S. farm population since the Second World War. Even in the No 1 ag district, Nebraska’s 3rd District, the number of farm operators amount to 10 percent of the total population. Over the decades, farm groups have punched above their weight in Congress, partly by coalition building and partly by the vibrant role of the food and fiber sector. By some measurements, agriculture has a role in 16 million jobs.
USDA’s rankings of congressional districts are available here. Table 1 is number of farms. Table 20 is value of sales. There are 63 tables that sort farmers and production by various metrics.