This article was downloaded by: [Universita degli Studi di Torino] On: 24 September 2012, At: 03:55 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Scandinavian Journal of Forest Research Publication details, including instructions for aut hors and subscription information: http:/ / www.tandfonline.com/ loi/ sfor20 Age and growth patterns of old Norway spruce trees in Trillemarka forest, Norway Daniele Castagneri a , Ken Olaf Storaunet b & Jørund Rolstad b a Department of AgroSelviTer, University of Turin, Grugliasco, Italy b Norwegian Forest Research Institute, Høgskoleveien 12, NO-1432, Ås, Norway Accepted author version posted online: 10 Sep 2012.Version of record first published: 20 Sep 2012. To cite this article: Daniele Castagneri, Ken Olaf Storaunet & Jørund Rolstad (2012): Age and growth patterns of old Norway spruce trees in Trillemarka forest, Norway, Scandinavian Journal of Forest Research, DOI:10.1080/ 02827581.2012.724082 To link to this article: http:/ / dx.doi.org/ 10.1080/ 02827581.2012.724082 PLEASE SCROLL DOWN FOR ARTI CLE Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions This article may be used for research, teaching, and private study purposes. Any substantial or system atic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Scandinavian Journal of Forest Research 2012, 1Á9, iFirst article ORIGINAL ARTICLE Age and growth patterns of old Norway spruce trees in Trillemarka forest, Norway DANIELE CASTAGNERI1, KEN OLAF STORAUNET2 & JØRUND ROLSTAD2 1Department of AgroSelviTer, University of Turin, Grugliasco, Italy, and 2Norwegian Forest Research Institute, Høgskoleveien 12, NO-1432 A˚s, Norway Abstract Old trees represent key features of old-growth forests and are important elements for maintaining biodiversity. Due to extensive human exploitation of Fennoscandian boreal forests during several centuries, old Norway spruce trees have become exceedingly rare. We analysed 91 spruce trees in Trillemarka Nature Reserve, southern Norway, to investigate (1) the maximum age of living trees, (2) growth rates of different-age trees and (3) growth trends in very old trees. Increment cores were taken from trees in selected old-growth stands located at 700Á850 m a.s.l. Twelve spruce trees had an estimated total age of 400 years, the oldest one being 529 years and presumably the oldest known still living Norway spruce in northern Europe. A negative relationship between growth rate (basal area increment) and total age was observed, being most distinct for growth rates at 126Á275 years and less marked for early stage growth (26Á75 years). Thus, high age apparently was related more to low growth rates at adult and old stages of life rather than at the earlier stage. Among the trees 400 years, many of them did not show growth decrease with advancing age, indicating that ageing did not reduce growth. We conclude that the maximum age of stand-forming Fennoscandian Norway spruce trees would be in the range of 500Á600 years. Keywords: Age, dendrochronology, longevity, Picea abies, tree growth. Introduction ever, species-specific maximum ages can be strongly influenced by extreme growth conditions. For exam- Old trees are key components of old-growth forest, ple, Larson (2001) found that Thuja occidentalis L. constituting unique habitats for many rare species. can live for more than 1600 years on steep rocky cliffs, They also represent exceptional archives of past forest dynamics and climate (Arnan et al., 2012; Lie et al., but rarely exceeds 400 years on fertile sites. 2009; Nascimbene et al., 2009; Schweingruber & Recently, there has been increased interest in what Wirth, 2009). However, even in old-growth forests, controls the lifespan of trees, including possible Downloaded by [Universita degli Studi di Torino] at 03:55 24 September 2012 individuals close to maximum age are extremely rare. effects of ageing (Pen˜uelas, 2005; Pen˜uelas & Such trees have always fascinated researchers, and Munne`-Bosch, 2010). Across taxa, there is evidence several surveys have been conducted to find the of a negative relationship between growth rate and oldest individuals of different tree species. World- lifespan (Metcalfe & Monaghan, 2003), indicating wide, there are about 20 species that exceed 1000 that slow growth prolongs life expectancy. Regarding years of age, with Pinus longaeva Bailey approaching possible age effects, some studies indicate that signs 5000 years in western US timberlines (Brown, 1996; of senescence (e.g. increase of hydraulic resistance, Currey, 1965; Schulman, 1958) as the oldest. In decrease of photosynthetic rate and reduction of Europe, the most widespread species reach xylogenesis duration) may be more related to size maximum ages between 400 and 700 years (Fagus than age (Mencuccini et al., 2005; Noode´n & sylvatica L., Picea abies (L.) Karst., Pinus sylvestris L., Leopold, 1988; Pen˜uelas, 2005; Petit et al., 2008). Quercus spp.) (Schweingruber & Wirth, 2009), Whereas studies on physiological ageing processes of whereas the European larch (Larix decidua Mill.) plant tissues are rather common, relationships may reach 1000 years (Nola & Motta, 1996). How- between age and growth at the level of whole-tree Correspondence: Daniele Castagneri, Department of AgroSelviTer, University of Turin, I-10095 Grugliasco (TO), Italy, E-mail: [email protected] (Received 29 March 2012; accepted 20 August 2012) ISSN 0282-7581 print/ISSN 1651-1891 online # 2012 Taylor & Francis http://dx.doi.org/10.1080/02827581.2012.724082 2 D. Castagneri et al. have received less attention (Issartel & Coiffard, pine (P. sylvestris L.) dominates on low productive 2011; Matthes et al., 2008; Schweingruber & Wirth, sites, with a field layer of the Calluna vulgaris Á 2009). A reduced growth in gross volume as trees Vaccinium uliginosum type, often with some Norway approach old age is generally assumed (Duchesne spruce (P. abies) admixed in the understory. Norway et al., 2003; Pen˜uelas, 2005). However, as the spruce dominates on more productive slopes with a meristem regenerates every vegetative season, some field layer of Vaccinium myrtillus (L.). Deciduous tree authors point out that the concept of senescence as species (Alnus incana (L.) Moench, Betula pubescens an endogenously controlled degenerative process Ehrh., Populus tremula L., Sorbus aucuparia L.) occur does not apply to trees (Connor & Lanner, 1990; sporadically. Larson, 2001; Noode´n & Leopold, 1988; Pen˜uelas & Trillemarka forest represents one of a few areas Munne`-Bosch, 2010; Rossi et al., 2008). that host a certain number of very old Norway To elaborate on the age and growth patterns of spruce trees in southern Fennoscandia. Historically, Norway spruce (P.abies (L.) Karst.), one of the most the area has been utilised by human for centuries, widespread tree species in Europe, we performed a including summer dairy farming, grazing by domes- dendrochronological analysis in Trillemarka Nature tic animals, slash-and-burn cultivation and high- Reserve, southern Norway. Trillemarka is one of few grading timber harvesting (Mørch, 1954; Storaunet areas in northern Europe that are little influenced by et al., 2005a, 2005b; Toeneiet et al., 2007). The fire industrial forestry, and where a fair number of very history in Trillemarka shows an increased fire old spruce trees still persist. Our first goal was to frequency during the 1600s and 1700s due to assess the maximum age of Norway spruce trees in anthropogenic influence (Blanck, Storaunet & the Trillemarka forest. Establishing the longevity of Rolstad, unpublished data). However, far less rem- one of the pivotal tree species of the Eurasian boreal nant fire scarred pine stumps are found in the forest is important in understanding forest dynamics, spruce-dominated stands compared to the pine and as a reference for natural forest management forest. Thus, quite a few core areas of the Reserve and conservation. Second, we wanted to see if slow have been identified as little influenced by humans, growth is a prerequisite for getting very old. This has some of which showing high structural diversity already been observed in a few forest stands regarding tree composition, age and size distribu- (Di Filippo et al., 2012; Ro¨theli et al., 2012), and tion, and dead wood characteristics (Bendiksen, can have important repercussions in understanding 2004; Hofton, 2003, 2004). This illustrates the growth and mortality processes. Finally, we analysed gradient in historic human influence, where less trends in growth rate of trees approaching their utilised areas generally are found at higher altitudes maximum age, to see if ageing negatively affected and farther away from main valleys and historic growth. summer dairy farms. In such core areas we expected to find very old trees. Materials and methods Trillemarka