This module introduces plant and crop models approaches. General considerations about models are first listed, leading to distinguish descriptive models from causal ones (focus is given to causal models).

Principles of various approaches are then shortly introduced, with their pro and cons:

- Process based models, issued from agronomy, modelling plant production at stand level

- Structural plant models, offering usually 3D representations, defined at the plant individual level

- Functional structural plant models, trying to combine plant production and plant structure modelling, also defined at plant individual level.

These approaches reflect a wide range of models developed in the communities' interests by plant growth models, in agronomy, forestry, up to entertainment.