source (not completed yet)

http://www.onetonline.org/link/summary/11-9013.02
http://www.umsl.edu/services/govdocs/ooh20022003/ocos285.htm
http://www.careerinfonet.org/occ_rep.asp?optstatus=011000000&soccode=119013&id=1&nodeid=2&stfips=45&search=Go
http://www.bls.gov/ooh/farming-fishing-and-forestry/agricultural-workers.htm#tab-4