Demand for farm products grew, and the cost of marketing them shrank, between 1860 and 1880. The resulting commercialization of Midwestern agriculture has been widely discussed, but the production strategies that farmers pursued have not been adequately described or modeled. I find that an endowment-contingent model of crop choice provides a consistent explanation for farm production strategies at the micro-level on Missouri farms. The results call for a re-examination of the conventional wisdom that commercialization fostered specialization at the regional level.