In this module, we have revised some key elements of ecology that help us to understand the growth pattern of trees and of forest stands, and of the role of disturbance in initiating regeneration. You will have refreshed your knowledge of seeder and sprouter mechanisms for tree regeneration following disturbance, and will be able to comment on typical stand structures that result from these two methods of regeneration. One way of looking at forests is that they are systems that capture light energy in the form of organic matter. In this way forests provide energy for all the heterotrophic life forms (most bacteria, all fungi, and all fauna) in an ecosystem. Maximizing or optimizing energy capture by forests is a central aim in restoring forests and in plantation development. Measuring or estimating net primary productivity (NPP) is one way to measure energy capture by a forest system. By understanding the importance of nutrients in limiting NPP, you have a good basis from which to manage forest restoration and plantation development projects.