Best Practice Knowledge Base
2.2 Thinning
Thinning in a spruce stand. Schwarzwald, Germany © Hernán Serrano-León
Thinning is a silvicultural practice of selectively removing trees to reduce competition that enhances the growth and health of remaining trees. In structurally and compositionally poor stands, thinning can be used to improve structural diversity, promote natural regeneration, and create light and nutrient conditions favorable for understory development and biodiversity recovery. It can also mitigate risks like wildfire or pest outbreaks, helping transition degraded forests toward more natural, resilient states.
I. Guidelines
| Nº | Title | Author | Year | Focus Region | Language | Summary | Link |
| 1 | Thinning practice: A silvicultural guide | Kerr and Haufe | 2011 | UK | English | Introduction and detailed guidelines for thinning | https://www.forestresearch.gov.uk/publications/thinning-practice-a-silvicultural-guide/ |
| 2 | Handbook of commercial thinning in Alberta | Forest Growth | 2023 | US | English | Detailed guide for commercial thinning | https://fgrow.ca/wp-content/uploads/sites/3/2023/02/Version-1-Handbook-for-Commercial-Thinning-in-Alberta.pdf |
| 3 | Interim guidance for commercial thinning | British Columbia Ministry of Forests, Lands, Natural Resource Operations and Rural Development | 2021 | British Columbia | English | Detailed guide for commercial thinning | https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/forestry/stand-tending/interim_guidance_for_commercial_thinning.pdf |
| 4 | Durchforstungshilfe 2010 | FVA Baden-Württemberg | 2010 | Germany | German | Technical guide for the planning of a thinning approach in even- and uneven-aged stands | https://itga.ie/images/pdf/IrishThinningProtocol.pdf |
II. Books or book chapters
| Nº | Title | Author | Chapter | Chapter author | Year | Focus region | Language | Summary | Link |
| 1 | Introducción a la selvicultura general | González Molina | Tratamientos de mejora: Limpias, clareos y claras | - | 2005 | Spain | Spanish | Definition and introduction to thinning | https://publicaciones.unileon.es/product/introduccion-a-la-selvicultura-general/ |
| 2 | Introducción a la selvicultura general | González Molina | Tipos de claras | - | 2005 | Spain | Spanish | Description of different thinning approaches | https://publicaciones.unileon.es/product/introduccion-a-la-selvicultura-general/ |
| 3 | Selvicoltura generale | Piussi and Alberti | I tagli intercalari: I diradamenti | - | 2015 | Italy | Italian | Description of different thinning approaches | - |
| 4 | Plantation silviculture in Europe | Savill et al. | Spacing, thinning, pruning, and rotation length: Thinning | - | 1997 | Europe | English | Basic technical indications for thinning in the context of plantation forests | https://global.oup.com/academic/product/plantation-silviculture-in-europe-9780198549086?cc=us&lang=en&# |
| 5 | Silviculture: Concepts and applications | Nyland | Thinning and its effects on stand development | - | 2016 | World | English | - | https://www.waveland.com/browse.php?t=416 |
| 6 | Silviculture: Concepts and applications | Nyland | Methods of thinning | - | 2016 | World | English | - | https://www.waveland.com/browse.php?t=416 |
| 7 | Silviculture: Concepts and applications | Nyland | Thinning regimes in the even-aged silvicultural system | - | 2016 | World | English | - | https://www.waveland.com/browse.php?t=416 |
| 8 | Mixed species forests | Pretsch et al. | Tending and thinning in mixtures | - | 2017 | World | English | Decscription of thinning procedures in the context of mixed plantations | https://link.springer.com/book/10.1007/978-3-662-54553-9 |
| 9 | Grundriss des Waldbaus | Burschell and Huss | Bestandeserziehung-Bestandespflege - Durchforstung | - | 2004 | Europe | German | Comprehensive introduction and guidelines for thinning, for different stand types of central Europe | - |
| 10 | Waldbau auf Ökologischer Grundlage | Bartsch et al. | Bestandespflege: Durchforstung | - | 2020 | Germany | German | Introduction and guidelines for thinning | https://www.utb.de/doi/book/10.36198/9783838587547 |
| 11 | The practice of silviculture: Applied forest ecology | Ashton and Kelty | Tree and stand growth: The effects of thinning on stand production; The effects of thinning on economic yield of stands | - | 2017 | World | English | - | https://www.wiley-vch.de/de/fachgebiete/naturwissenschaften/the-practice-of-silviculture-978-1-119-27095-9 |
| 12 | The practice of silviculture: Applied forest ecology | Ashton and Kelty | Methods of thinning | - | 2017 | World | English | - | https://www.wiley-vch.de/de/fachgebiete/naturwissenschaften/the-practice-of-silviculture-978-1-119-27095-9 |
| 13 | The practice of silviculture: Applied forest ecology | Ashton and Kelty | Quantitative thinning: Theory and application | - | 2017 | World | English | - | https://www.wiley-vch.de/de/fachgebiete/naturwissenschaften/the-practice-of-silviculture-978-1-119-27095-9 |
III. Scientific articles
| Nº | Title | Author | Year | Focus region | Language | Type | Summary | Link |
| 1 | Opportunities and limitations of thinning to increase resistance and resilience of trees and forests to global change | Moreau et al. | 2022 | World | English | Narrative review | Effects of thinning on stand- and tree-level resistance and resilience to drought, fire, pests, and wind. | https://doi.org/10.1093/forestry/cpac010 |
| 2 | Establishment and growth of native hardwood and conifer seedlings underplanted in thinned Douglas-fir stands | Maas-Hebner et al. | 2005 | US | English | Experiment | Effects of different thinning intensities on the performance of underplanted hardwood species | https://www.sciencedirect.com/science/article/pii/S037811270500023X |
| 3 | Effects of stand conversion by thinning and underplanting on water and element fluxes of a pine ecosystem (P. sylvestris L.) on lignite mine spoil | Knoche | 2005 | Germany | English | Experiment | Effects of thinning and underplanting on water and element fluxes in Pinus sylvestris stands | https://www.sciencedirect.com/science/article/pii/S0378112705002008 |
| 4 | Potential of forest thinning to mitigate drought stress: A meta-analysis | Sohn et al. | 2016 | World | English | Experiment | Effects of thinning on water balance | https://www.sciencedirect.com/science/article/pii/S0378112716304029 |
| 5 | Biodiversity response to intensive biomass production from forest thinning in North American forests – A meta-analysis | Verschuyl et al. | 2011 | US | English | Systematic review | Effects of commercial thinning on biodiversity in the US | https://www.sciencedirect.com/science/article/pii/S0378112710006110 |
| 6 | A global synthesis on the effects of thinning on hydrological processes: Implications for forest management | Del Campo et al. | 2022 | World | English | Systematic review | Effects of thinning on hydroplogical processes, with an emphasis on rainfall | https://www.sciencedirect.com/science/article/pii/S0378112722003188 |
| 7 | Silvicultural measures to increase the mechanical stability of pure secondary Norway spruce stands before conversion | Slodiak and Novak | 2006 | Czech Republic | English | Experiment | Evaluates the effect of different thinning treatments on Norway spruce stand stability prior to harvesting for conversion | https://www.sciencedirect.com/science/article/pii/S037811270500784X?casa_token=X-sq2q69B0kAAAAA:hzyRTAuukAMTr5Om2fnvNz-2KMGyZBBYag8JiZxHPs2rgTEivBRrqiA065T-IrMCAvJfFfZcdg |
| 8 | Silvicultural measures to increase the mechanical stability of pure secondary Norway spruce stands before conversion | Slodiak and Novak | 2006 | Czech Republic | English | Experiment | Evaluates the effect of different thinning treatments on Norway spruce stand stability prior to harvesting for conversion | https://www.sciencedirect.com/science/article/pii/S037811270500784X?casa_token=X-sq2q69B0kAAAAA:hzyRTAuukAMTr5Om2fnvNz-2KMGyZBBYag8JiZxHPs2rgTEivBRrqiA065T-IrMCAvJfFfZcdg |