Human labor is the primary factor of production in indigenous agricultural systems, yet the organization and scheduling of labor, and effect of agricultural intensification on these processes, remain poorly understood. While most theoretical and empirical studies have emphasized overall labor input and efficiency, this study of the Kofyar of Nigeria analyzes the scheduling and mobilization of labor in ecological context. Detailed labor diaries for a sample of households over an entire agricultural cycle reveal intricate schedules that balance the labor demands of a variable crop complex with a set of complementary mechanisms for mobilizing labor. With rising population density and market impetus, the Kofyar have increased gross labor inputs, adjusted crop mixes to reduce weekly fluctuations in labor, and extended the agricultural season. Labor demands are met by three social mechanisms of labor mobilization, which offer varying sizes of labor pool, degree of flexibility, and type of compensation.