The description of Simplot you posted may be an ‘agribusiness’, but it is not a description of farming, corporate or otherwise.
Normally, food processors buy or contract produce from farmers and do not own the land or raise crops themselves. Many states prevent or discourage food processor ownership of land used for crop or livestock production.
JR Simplot farms about 83,000 acres. I would actually consider them a corporate farm even though they are family owned. I buy crop protection materials from their retail outlet here in California.