Following the establishment of the plantation project, when all the trees are in the ground, the options for increasing the value of the wood grown become more limited. Ways to increase the profitability of the plantation include (1) manipulation of site resources to increase the volume or mass of trees and (2) silviculture to improve the value of the trees. Among the crucial site resources – light, water, and nutrients – it is usually only nutrients that can be managed to improve tree growth rates. This topic explores the application of nutrients to increase plantation productivity in the context of the allocation of net primary productivity through different stages of forest stand development. This approach emphasizes the importance and role of nutrient cycling in natural forest stands in building site resources and maintaining forest productivity. These principles are applied to intensively established plantation forests to highlight the importance of tree residues, produced during the life of the plantation and at harvest, in maintaining and building plantation productivity. Lastly, the silvicultural techniques of thinning and pruning that increase the value of trees grown are discussed. This includes the theory and management of tree growing space through thinning and the production of more clear-wood (knot-free timber) through pruning.
Please view the following video lecture and video for this topic.
3.3 Lecture: Plantation Productivity – Site Resources and Silviculture
3.3 Video: Replanting Considerations – Coppicing in Bluegum Forestry
Topic 3 Reflection Questions
Please answer the following self-reflection questions. After formulating your answers, you may post them online at the Knowledge Café for this course as a way to share your ideas and glean knowledge from other students’ responses.
- Do nutrients added as fertilizers to tree plantations add to long-term site resources?
- How does the allocation of net primary productivity (NPP) change through the development of a natural forest stand? How can this pattern of NPP allocation inform the timing of fertilizer application to tree plantations and the management of tree residues between plantation rotations?
- How can the management of basal area be applied to thinning practice? Give examples from the published literature.
Binkley, D. (1986). Plantation Nutrition Management. John Wiley & Sons, Inc. ISBN 0471818836
Bowen, G.D., & Nambiar, E.K.S. (1984). Nutrition of Plantation Forests. Academic Press. ISBN-10: 0121209806; ISBN-13: 978-0121209803
Articles in Journals
Tutua, S.S., Xu, Z.H., Blumfield, T.J., & Bubb, K.A. (2008). Long-term impacts of harvest residue management on nutrition, growth and productivity of an exotic pine plantation of sub-tropical Australia. Forest Ecology and Management, 256 (4), 741-748.