Current plant growth models, applications, and data: Mathematical descriptions of plant growth and development; Applied plant growth models for grazinglands, forests and crops; Data for plant growth modeling, and evaluation. Parte II - Forescasting and estimating plant yield: Choosing a basis for yield forecasts and estimates; Forecasting andestimating effects of weather on yield; The scale problem, modeling plant yield over time and space. Part III - The future of applied plant growth modeling: The future of applied plant growth modeling.