Cotton production efficiency could be enhanced by a system of monitoring and responding to subtle variation in plant growth and development. We are evaluating use of a vigor index and apical nodal development as means of detecting variation. The vigor index provides a measure of growth rate of pre-flowering plants by comparing number of main stem nodes (physiological age) with plant height (speed of growth). By adjusting early growth to conform with standard vigor indices, optimum plant structure at flowering should be achieved. After flowering, growth status of plants can be monitored by counting the number of main stem nodes above first position white flower (NAWF). NAWF is a composite measure of the effects of all production factors that influence fruiting of the plant. Pre-flowering factors mainly influence the number of NAWF at first flower while post-flowering factors influence rate of change in NAWF. Using NAWF of 5.0 as an indicator of the last effective boll population, end-of-season factors can be sequenced by heat units required for those bolls to reach critical maturity status. Progress is being made to integrate vigor index and apical nodal development measurement into a plant management system.