Stocking control concepts in uneven-aged silviculture

Stocking control refers to forest management operations that alter the number and arrangement of trees within a stand and is a central element of uneven-aged silviculture. Many alternative stocking control approaches have been developed for uneven-aged stands. Four methods are presented that represent a contrast in complexity and emphasis, but that conceptually build on each other. All are assumed to be tools for allocation of growing space. The BDq approach builds on a reverse-J diameter distribution that serves as a target stand structure. The Plenter system is similar to the BDq approach as it uses a diameter distribution to represent stand structure but provides more flexibility for structures with different growth patterns. Stand density index can be allocated among diameter classes to form a variety of structures. Similarly, leaf area index can be allocated among age classes or canopy strata without the constraints of a reverse-J diameter distribution. Other methods for controlling stocking in uneven-aged stands exist and many undoubtedly represent sound approaches to management. The trend in the four approaches described here is towards a better understanding of stand dynamics and greater flexibility for diverse structural goals.