diameter at breast height growth; crown release; crop tree silviculture; crown development
Abstract :
[en] Forest health problems arising from climate change, pests and pathogens are a threat to the
main timber tree species. As a result, silver birch (Betula pendula Roth) has become a precious asset for meeting oncoming forestry challenges in western Europe. However, silviculture guidelines to produce high-value birch logs in this region are lacking. Producing large-sized birch trunks requires crown release, i.e., removing crown competitors around selected target trees. These interventions are currently seldom carried out or else too late when the growth potential of the trees has already diminished. This study set out to ascertain the diameter at breast height (dbh) that could be reached by crown-released birch, determine dbh-associated crown diameters, and further characterize the gain obtained from early crown release on birch dbh growth. We measured 704 birch trees that had undergone crown release in 38 naturally regenerated pure birch stands in southern Belgium and in northeastern France. We then evaluated the variation in stem and crown diameter, and analyzed increments in response to the earliness of the interventions in three subsamples, also compared with control target birch. We found that trees with a dbh of 50 cm could be grown within 60 years.
Based on crown diameter, to produce 40, 50 and 60 cm dbh trunk, the distance required between
target birch trees at the end of the rotation was around 8, 10 and 12 m. With no intervention and in ordinary dense birch regenerations, the dbh increment was found to decline once the stand reached age 4–7 years. Starting crown release in stands aged 4–5 years can double the dbh increment of target trees and provide a continual gain that may last up to 20 years. When birch crowns are released after 9–12 years, it may already be too late for them to recover their best growth rate. Our contribution should help complete emerging guidelines in support of birch silviculture development.
Lindner, M.; Maroschek, M.; Netherer, S.; Kremer, A.; Barbati, A.; Garcia-Gonzalo, J.; Seidl, R.; Delzon, S.; Corona, P.; Kolström, M.; et al. Climate change impacts, adaptive capacity, and vulnerability of European forest ecosystems. For. Ecol. Manag. 2010, 259, 698–709. [CrossRef]
Brang, P.; Spathelf, P.; Larsen, J.B.; Bauhus, J.; Boncına, A.; Chauvin, C.; Drössler, L.; Garcıa-Güemes, C.; Heiri, C.; Kerr, G.; et al. Suitability of close-to-nature silviculture for adapting temperate European forests to climate change. Forestry 2014, 87, 492–503. [CrossRef]
Jucker, T.; Bouriaud, O.; Avăcăriei, D.; Coomes, D.A. Stabilizing effects of diversity on aboveground wood production in forest ecosystems: Linking patterns and processes. Ecol. Lett. 2014, 17, 1560–1569. [CrossRef] [PubMed]
Messier, C.; Bauhus, J.; Doyon, F.; Maure, F.; Sousa-Silva, R.; Nolet, P.; Mina, M.; Aquilué, N.; Fortin, M.-J.; Puettmann, K. The functional complex network approach to foster forest resilience to global changes. Forest Ecosyst. 2019, 16. [CrossRef]
Dubois, H.; Latte, N.; Lecomte, H.; Claessens, H. Le bouleau, une essence qui s’impose. Description de la ressource dans son aire de distribution. For. Nat. 2016, 140, 44–58. (In French)
Dubois, H.; Verkasalo, E.; Claessens, H. Potential of Birch (Betula pendula Roth and B. pubescens Ehrh.) for Forestry and Forest-based Industry Sector within the Changing Climatic and Socio-economic Context of Western Europe. Forests 2020, 11, 336. [CrossRef]
Perala, D.A.; Alm, A.A. Reproductive ecology of birch: A review. For. Ecol. Manag. 1990, 32, 1–38. [CrossRef]
Niemistö, P.; Viherä-Aarnio, A.; Velling, P.; Heräjärvi, H.; Verkasalo, E. Koivun Kasvatus ja Käyttö. [Silviculture and Use of Birch]; Finnish Forest Research Institute and Metsäkustannus Ltd.: Metsäntutkimuslaitos ja Metsäkustannus, Finland, 2008; p. 254. (In Finnish)
Hein, S.; Winterhalter, D.; Wilhelm, G.J.; Kohnle, U. Wertholzproduktion mit der Sandbirke (Betula pendula Roth): Waldbauliche Moglichkeiten und Grenzen. Allg. For. Jagdztg. 2009, 180, 206–219. (In German)
Hynynen, J.; Niemistö, P.; Viherä-Aarnio, A.; Brunner, A.; Hein, S.; Velling, P. Silviculture of birch (Betula pendula Roth and Betula pubescens Ehrh.) in northern Europe. Forestry 2010, 83, 103–119. [CrossRef]
Kleinschmit, A. The Broadeaf Citizen—Broadening the innovatice use of European hardwoods. In Proceedings of the 6th International Scientific Conference on Hardwood Processing, Lahti, Finland, 25–28 September 2017; Möttönen, V., Heinonen, E., Eds.; Natural Resources Institute Finland: Helsinki, Finland, 2017; pp. 14–15.
Teischinger, A. From Forest to Wood Production—A selection of challenges and opportunities for innovative hardwood utilization. In Proceedings of the 6th International Scientific Conference on Hardwood Processing, Lahti, Finland, 25–28 September 2017; Möttönen, V., Heinonen, E., Eds.; Natural Resources Institute Finland: Helsinki, Finland, 2017; p. 13.
Vanhellemont, M.; Van Acker, J.; Verheyen, K. Exploring life growth patterns in birch (Betula pendula). Scand. J. For. Res. 2016, 31, 7. [CrossRef]
Frauendorfer, R. Forstliche Hilfstafeln Schriftenreihe der forstlichen Bundes-Versuchsans-talt Mariabrunn Band II; Kommissionsverlag der Österreichischen Staatsdruckerei: Wien, Austria, 1954; p. 168. (In German)
Eriksson, H.; Johansson, U.; Kiviste, A. A site-index model for pure and mixed stands of Betula pendula and Betula pubescens in Sweden. Scand. J. For. Res. 1997, 12, 149–156. [CrossRef]
Diéguez-Aranda, U.; Grandas-Arias, J.A.; Álvarez-González, J.G.; Gadow, K.v. Site quality curves for birch stands in north-western Spain. Silva Fenn. 2006, 40, 631–644. [CrossRef]
Lemaire, J. Contribution à l’étude de la sylviculture du Betula pendula Roth. La sylviculture du Betulla pendula Roth au Bois de Lauzelle (Louvain-la-Neuve). Master’s Thesis, Université Catholique de Louvain, Louvain-la-Neuve, Belgium, 1998; p. 175. (In French)
Zâlîtis, T.; Zâlîtis, P. Growth of Young Stands of Silver Birch (Betula pendula Roth.) Depending on Pre-Commercial Thinning Intensity. Baltic Forestry 2007, 13, 61–67.
Rytter, L.; Werner, M. Influence of early thinning in broadleaved stands on development of remaining stems. Scand. J. For. Res. 2007, 22, 198–210. [CrossRef]
Rytter, L. Growth dynamics of hardwood stands during the precommercial thinning phase—Recovery of retained stems after competition release. For. Ecol. Manag. 2013, 302, 264–272. [CrossRef]
Prévosto, B.; Agrech, G. Dynamique et typologie des accrus. Le cas des bétulaies dans la chaîne des. Puys. Rev. For. Fr. 1998, 50, 46–58. (In French)
Prévosto, B.; Coquillard, P.; Gueugnot, J. Growth models of silver birch (Betula pendula Roth.) on two volcanic mountains in the French Massif Central. Plant Ecol. 1999, 144, 231–242. [CrossRef]
Cameron, A.D. Managing birch woodlands for the production of quality timber. Forestry 1996, 69, 357–371. [CrossRef]
de Champs, J. Mesures sylvicoles préventives. Rev. For. Fr. 1987, 39, 313–322. (In French) [CrossRef]
Verkasalo, E. Hieskoivun laatu vaneripuuna. Abstract: Quality of White Birch (Betula pubescens Ehrh.) for Veneer and Plywood. Dissertation for D.For. in wood science and forest products. Department of Logging and Utilization of Forest Resources, University of Helsinki, Finland. Finn. For. Res. Inst. Res. Pap. 1997, 632, 483. (In Finnish)
Wilhelm, G.J.; Rieger, H. Naturnahe Waldwirtschaft—Mit der QD-Strategie: Eine Strategie für Den Qualitätsgeleiteten und Schonenden Gebrauch des Waldes Unter Achtung der Gesamten Lebewelt; Eugen Ulme KG: Stuttgart, Germany, 2013; p. 207. (In German)
Luostarinen, K.; Verkasalo, E. Birch as Sawn Timber and in Mechanical Further Processing in Finland. A Literature Study. Silva Fenn. Monogr. 2000, 1, 40.
Niemistö, P.; Kilpeläinen, H.; Heräjärvi, H. Effect of pruning season and tool on knot occlusion and stem discolouration in Betula pendula—Situation five years after pruning. Silva Fenn. 2019, 53, 29. [CrossRef]
Cameron, A.D.; Dunham, R.A.; Petty, J.A. The effects of heavy thinning on stem quality and timber properties of silver birch (Betula pendula Roth). Forestry 1995, 68, 275–285. [CrossRef]
Gómez-García, E.; Crecente-Campo, F.; Tobin, B.; Hawkins, M.; Nieuwenhuis, M.; Dieguez-Aranda, U. A dynamic volume and biomass growth model system for even-aged downy birch stands in south-western Europe. Forestry 2014, 87, 165–176. [CrossRef]
Petit, S.; Claessens, H.; Vincke, C.; Ponette, Q.; Marchal, D. Le Fichier écologique des essences, version 2.0. For. Nat 2017, 143, 12–19. (In French)
Wood, J.E.; Von Althen, F.W.; Mitchell, E.G. Crown release improves growth of 20-year-old Betula alleghaniensis in tolerant northern hardwood stands. New For. 1996, 12, 87–99. [CrossRef]
Meng, S.X.; Rudnicki, M.; Lieffers, V.J.; Reid, D.B.; Silins, U. Preventing crown collisions increases the crown cover and leaf area of maturing lodgepole pine. J. Ecol. 2006, 94, 681–686. [CrossRef]
R Core Team. R: A Language and Environment for Statistical Computing; R Foundation for Statistical Computing: Vienna, Austria, 2017; Available online: https://www.R-project.org/(accessed on 25 March 2021).
Wickham, H.; François, R.; Henry, L.; Müller, K. dplyr: A Grammar of Data Manipulation. R Package Version 0.8.0.1. 2019. Available online: https://CRAN.R-project.org/package=dplyr (accessed on 25 March 2021).
Pinheiro, J.; Bates, D.; DebRoy, S.; Sarkar, D.; R Core Team. nlme: Linear and Nonlinear Mixed Effects Models. R Package Version 3.1-131. 2017. Available online: https://CRAN.R-project.org/package=nlme (accessed on 25 March 2021).
Wickham, H. ggplot2: Elegant Graphics for Data Analysis, 2nd ed.; Springer: New York, NY, USA, 2016; p. 260.
Hemery, G.E.; Savill, P.S.; Pryor, S.N. Applications of the crown diameter–stem diameter relationship for different species of broadleaved trees. For. Ecol. Manag. 2005, 215, 285–294. [CrossRef]
Cole, W.G.; Lorimer, C.G. Predicting tree growth from crown variables in managed northern hardwood stands. For. Ecol. Manag. 1994, 67, 159–175. [CrossRef]
HOMBURG1. Wertholzperspektiven im Biosphärenwald, HOMBURG1, Homburg, Germany; Press Article 13 May 2016. Available online: http://homburg1.de/wertholzperspektiven-im-biosphaerenwald-10909/(accessed on 25 March 2021). (In German).
Paillet, Y.; Debaive, N.; Archaux, F.; Cateau, E.; Gilg, O.; Guilbert, E. Nothing else matters? Tree diameter and living status have more effects than biogeoclimatic context on microhabitat number and occurrence: An analysis in French forest reserves. PLoS ONE 2019, 14, e216500. [CrossRef]
Claessens, H.; Oosterbaan, A.; Savill, P.; Rondeux, J. A review of the characteristics of black alder (Alnus glutinosa (L.) Gaertn.) and their implications for silvicultural practices. Forestry 2010, 83, 163–175. [CrossRef]
