[Pete_D]

The full report (https://www.cdc.gov/mmwr/volumes/67/wr/mm6745a1.htm?s_cid=mm...) says they're using the Standard Occupational Classification system (https://www.bls.gov/soc/). You can read the full definitions at https://www.bls.gov/soc/2010/2010_major_groups.htm; farm managers are at 11-9013, agricultural workers are under 45-2000. The distinction in this case seems to be whether or not someone working on a farm is mostly a manager or mostly a laborer.