| 1. |
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| 2. |
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| 3. |
- Attocchi, Giulia, et al.
(författare)
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Crown radius of pedunculate oak (Quercus robur L.) depending on stem size, stand density and site productivity
- 2015
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 30, s. 289-303
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Tidskriftsartikel (refereegranskat)abstract
- Crown size is a good indicator of the growth potential of trees and is often used in forest management for outlining thinning guidelines or constructing forest growth models. The aim of this study was to analyse mean crown radius as a function of stem size, stand density and site productivity in even-aged stands of pedunculate oak (Quercus robur L.). Data included measurements of 620 trees from 53 plots in nine thinning experiments and one operational stand in Sweden, Denmark and Great Britain, representing a wide spectrum of thinning practices ranging from the strictly unthinned control to extremely heavy thinning with essentially solitary trees. Three sets of models were constructed based on different predictor variables, including indicators of individual stem size (diameter at breast height, DBH), stand density/thinning grade (quadratic mean diameter and stand basal area) and site productivity (stand top height). Preliminary results indicated a significant effect of DBH and (nominal) thinning grade on crown radius. The response pattern of the final models indicated an increasing crown radius with increasing DBH, with increasing thinning grade (decreasing stand density) and with decreasing site productivity. The models are valid for predicting the crown radius of pedunculate oak in even-aged forest stands.
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| 4. |
- Bakys, Remigijus, et al.
(författare)
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Patterns and Severity of Crown Dieback in Young Even-Aged Stands of European Ash (Fraxinus excelsior L.) in Relation to Stand Density, Bud Flushing Phenotype, and Season
- 2013
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Ingår i: Plant Protection Science. - 1212-2580. ; 49, s. 120-126
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Tidskriftsartikel (refereegranskat)abstract
- The extent and temporal pattern of crown damage (attributed to Hymenoscyphus pseudoalbidus) in even-aged stands of Fraxinus excelsior in relation to bud flushing phenotype, stand density, and season was investigated. Data were collected in 2007 in four statistically designed thinning experiments located in 12-15-years old plantations of ash in Denmark. The study included 21 plots of four contrasting, residual stand densities: (1) 1700-5500 trees/ha (unthinned control plots), (2) 1500 trees/ha, (3) 500 trees/ha, and (4) 100-150 trees/ha. Assessments included estimation of flushing phenotype in May, followed by evaluation of severity of crown damage (percentage of crown killed) in June and September. Simultaneously, for each tree, the presence or absence of crown wilt and dead tops were recorded. The seasonal pattern of disease severity (average crown damage) was similar in all stands, and disregarding stand density the extent of tree crown damage increased significantly towards the end of the growing season (P < 0.005). Disease severity was the worst in unthinned plots, but otherwise unrelated to stand density. Late-flushing trees were most severely affected (P < 0.001). The observed patterns of disease severity are probably associated with ecological features of the pathogen that still remain largely unknown.
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| 5. |
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| 6. |
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| 7. |
- Hellsten, Sofie, et al.
(författare)
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Halter av baskatjoner, fosfor och kväve i stubbar i Sverige, Finland och Danmark
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Intresset för stubbskörd har ökat kraftigt på senare år, i takt med att efterfrågan på förnyelsebar energi ökat. Idag saknas det information om näringshalter i stubbar för att utröna effekten av stubbuttag på näringsbalans och försurning. Denna studie syftar till att ta fram ett större dataunderlag för halter i stubbar i Sverige, Finland och Danmark. Lokalerna representerar olika nedfallsnivåer, olika markförhållanden samt olika beståndsdata. Studien omfattar granstubbar från Sverige, Finland och Danmark, samt tall- och björkstubbar från Sverige. Följande näringsämnen ingick i studien: kväve (N), fosfor (P), kalcium (Ca), kalium (K), magnesium (Mg) och Natrium (Na). Resultaten indikerade att näringshalten i björkstubbar är högre jämfört med gran och tall. I Sverige och Finland noterades generellt sett högre näringshalter i stubbarna i södra delen av landet jämfört med norra delen, med undantag av fosfor. Näringshalterna är betydligt högre i stubbens och rötternas bark jämfört med veden. Halterna i rötterna ökade signifikant med minskad rotdiameter. För tallstubbarna i Jädraås noterades signifikant minskande näringshalter i stubbarna med åldern upp till 65 år för kväve, kalium, magnesium och fosfor. För Jädraås, som har den största representationen av ståndortsindex, noterades ökande halter med ståndortsindex för fosfor och kalium. Studien har medfört att dataunderlaget för halter i stubbar har ökat väsentligt vilket kan bidra till att minska osäkerheterna i beräkningar av näringsbalansen i skogsmark vid stubbskörd.
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| 8. |
- Hellsten, Sofie, et al.
(författare)
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Nutrient concentrations in stumps and coarse roots of Norway spruce, Scots pine and silver birch in Sweden, Finland and Denmark
- 2013
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Ingår i: Forest Ecology and Management. - : Elsevier BV. - 1872-7042 .- 0378-1127. ; 290, s. 40-48
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to evaluate the concentrations of nutrients in stumps and coarse roots in Norway spruce, Scots pine and silver birch in Sweden, Finland and Denmark, and to assess how nutrient concentrations vary with site characteristics, stand age and root size. Concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and sodium (Na) in spruce, pine and birch stumps were assessed in eight sites across Scandinavia. Nutrient concentrations were higher in birch than in spruce and pine. In Sweden and Finland, the nutrient concentrations were generally higher at the southern sites than at the sites located in the northern part of the countries, except for P. For all nutrients, concentrations were significantly higher in the bark of the stump and roots than in the wood. Furthermore, nutrient concentrations increased significantly with decreasing root diameter. This study did not demonstrate any correlations with stand age. Further studies are needed to provide a broader picture of how the stump nutrient contents vary with site characteristics and forest management practices to provide a better foundation for nutrient balance calculations when setting up recommendations for stump removal. (C) 2012 Elsevier B.V. All rights reserved.
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| 9. |
- Löf, Magnus, et al.
(författare)
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European Mixed Forests: definition and research perspectives
- 2014
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Ingår i: Forest Systems. - : Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA). - 2171-5068 .- 2171-9845. ; 23, s. 518-533
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Tidskriftsartikel (refereegranskat)abstract
- We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) briefly review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material and methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any developmental stage, sharing common resources (light, water, and/or soil nutrients). The presence of each of the component species is normally quantified as a proportion of the number of stems or of basal area, although volume, biomass or canopy cover as well as proportions by occupied stand area may be used for specific objectives. A variety of structures and patterns of mixtures can occur, and the interactions between the component species and their relative proportions may change over time. The research perspectives identified are (i) species interactions and responses to hazards, (ii) the concept of maximum density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields of research indicate that gradient studies, experimental design approaches, and model simulations are key topics providing new research opportunities.
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| 10. |
- Löf, Magnus, et al.
(författare)
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Management of oak forests: Striking a balance between timber production, biodiversity and cultural services
- 2016
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Ingår i: International Journal of Biodiversity Science, Ecosystem Services and Management. - : Informa UK Limited. - 2151-3732 .- 2151-3740. ; 12, s. 59-73
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Tidskriftsartikel (refereegranskat)abstract
- Identification of the ecosystem services provided by oak-dominated forests in southern Sweden is a prerequisite for ensuring their conservation and sustainable management. These forests seem well-suited for multiple-use forestry, but knowledge is limited regarding how to manage them for multiple uses. Management for the production of high-value timber species like oaks and management to conserve biodiversity, or for cultural services can be in conflict with each other. This study evaluates the capacity of three contrasting management regimes to provide societies with economic revenue from timber production, habitats for biodiversity and cultural services, and the study analyses associated trade-offs and synergies. The three regimes were: intensive oak timber production (A), combined management for both timber production and biodiversity (B) and biodiversity conservation without management intervention (C). We synthesized relevant scientific literature, governmental statistics and grey literature. Our assessments identified that Regime A provided the highest levels of economic returns and the lowest level of biodiversity. Regime C provided higher levels of habitat provision but at expense of wood production and cultural services. In contrast, Regime B provided a balanced delivery of timber production, biodiversity conservation and cultural services. We identified several stand-management options which provide comparatively synergistic outcomes in ecosystem services delivery. The use of these management options in combination with more traditional stand-management approaches may be a more effective means of achieving sustainable forest goods and services.
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| 11. |
- Ols, Clementine, et al.
(författare)
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Tarmvridrøn i Vendsyssel: fem års overlevelse, vækst og sundhed i en skovrejsningskultur på morænejord.
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 138-141
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Our investigation comprised a plot of 0.58 ha in a stand established by afforestation of farmland during spring 2007. The stand includes 16 different tree species (listed below), ten of which were planted at establishment, while the remaining six species were introduced as replacement planting or invaded spontaneously. Based on their frequency in this stand and their potential economic importance, we consider sycamore, cherry, walnut and Sorbus torminalis as the main species. The plot included a total of 116 Sorbus torminalis trees. The soil developed on sandy glacial till (type luvisol, or similar) with a fragipan at a depth of 40 cm (Figure 1). During the first five years after planting the height growth of Sorbus torminalis was almost the same as for ash and Norway spruce (Figure 3). Sycamore and cherry grew faster and ranged at the same level as Sitka spruce. For walnut the variation in height growth was substantial, but the best walnut trees grew almost as fast as ash. In 2010 and 2011 the average annual height growth of the 50 tallest trees ranged at 111-156 cm for sycamore, 90-126 cm for cherry, 71-113 cm for wild service tree, 87-96 cm for ash, 86 cm for walnut and 48-89 cm for Port Orford cedar / Lawson cypress (Table 2). So far, we have been unable to detect any statistically significant influence of topography or depth to the fragipan on height growth. The mortality of Sorbus torminalis was low (9 percent). The most significant problem for Sorbus torminalis was browsing by hare during a period of high snow cover in the winter of 2010 (Table 1 and Figure 2). This effectively reduced the height of the affected trees to 35-40 cm (Figure 3). No other tree species were browsed (the area was fenced). In 2012 we pre-selected 100 evenly distributed potential future crop trees per ha and 100 reserve trees. Out of these, only 9 trees were Sorbus torminalis, 23 were walnut, 31 were sycamore and 53 were cherry. During the selection, sycamore and cherry were avoided in favour of Sorbus torminalis and walnut. In the discussion we emphasize the challenge of managing a mixture of 16 different tree species. We point out the urgent need for timely regulation of the light conditions to favour Sorbus torminalis as well as walnut (Figure 4) and the need for early formative pruning as well as subsequent, regular high pruning to avoid inferior timber quality for the main species (Figure 5). We also point out that many of the 'additional' species should be regarded only as serving for the benefit of the hardwood timber species (sycamore, cherry, walnut, Sorbus torminalis). Finally, we conclude that the stand includes a suitable share of high-quality stems of sycamore and cherry, if Sorbus torminalis or walnut should fail completely.
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| 12. |
- Skovsgaard, Jens Peter
(författare)
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A review of European ash (Fraxinus excelsior L.): implications for silviculture
- 2011
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Ingår i: Forestry. - : Oxford University Press (OUP). - 0015-752X .- 1464-3626. ; 84, s. 133-148
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Forskningsöversikt (refereegranskat)abstract
- European ash (Fraxinus excelsior L.) is common throughout much of Europe and is a valuable broadleaved tree due to its ecological characteristics, outstanding wood properties and high economic value. It is a fast growing species, associated with several forest types and with a scattered distribution in many different forest communities. In this review, we sum up essential characteristics of European ash, relevant to the further development of silvicultural practices. The paper covers site requirements, regeneration and stand establishment, growth dynamics and wood quality, and health and robustness. The review also highlights implications for silviculture and summarizes new information on ash dieback, a phenomenon which is observed in many European countries. Ash grows best on fertile, pH-neutral, deep, freely drained soils and such sites should be favoured if the aim is for high quality timber. Ash grows well at wide spacing which can result in enlarged ring width and increased latewood percentage, making the wood denser and stronger. Relatively short rotations may be recommended, depending on site, to avoid black heart: for example, a harvesting diameter of 60 cm can be reached within 60-75 years at 60-80 ash crop trees per ha. Universal recommendations are therefore for wide spacing with heavy, regular thinning in order to get a large diameter within a relatively short rotation. The necessity for pruning depends on the stand density at establishment and the subsequent thinning regime.
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| 13. |
- Skovsgaard, Jens Peter
(författare)
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Afløvning af kirsebær
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 430-
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Many wild cherry trees in Denmark lost their foliage during the summer of 2013. Some appeared to be infected by cherry leaf spot (Blumeriella jaapii (Rehm) Arx), others by shothole blight (Stigmina carpophila ((Lév.) M.B. Ellis). Both fungi are generally harmless for cherry in the forest. Infected trees subsequently recover and should not be felled.
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| 14. |
- Skovsgaard, Jens Peter
(författare)
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Allgemeine Verbreitung
- 2013
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Ingår i: Elsbeere in Österreich – Monographie. - 9783902762221 ; , s. 35-46
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter reviews the post-glacial migration and distribution range of wild service tree (Sorbus torminalis (L.) Crantz). It is believed that wild service tree migrated into Europe from West Asia. Its current distribution is in many places associated with light-demanding forest types or coppice forestry. In central and northern parts of its distribution range the species is found mainly on warm sites and often with a southern or south-western exposure. In southern parts of its range and on very dry sites it is found mainly on northern slopes. Limiting factors appear to be low summer temperatures in the north and low precipitation in the south. The situation in Austria and neighbouring countries is being discussed in greater detail.
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| 15. |
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| 16. |
- Skovsgaard, Jens Peter
(författare)
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Biomass, basic density and biomass expansion factor functions for European beech (Fagus sylvatica L.) in Denmark
- 2012
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Ingår i: European Journal of Forest Research. - : Springer Science and Business Media LLC. - 1612-4669 .- 1612-4677. ; 131, s. 1035-1053
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to analyse the within-tree allocation of biomass and to develop biomass functions for above- and below-ground components of European beech in Denmark. Separate functions were developed for stem, branches, below-ground stump and root system, total above-ground biomass and total tree biomass. For each of these components or aggregate components, models were also developed for the average basic density of wood and bark. To enhance the versatility of the models, a function for estimating the biomass expansion factor (BEF) was also developed. The functions were based on 66 trees measured for total biomass. Model performance was evaluated based on 74 trees measured only for above-ground biomass. The trees were sampled in 18 different forest stands covering a wide range of tree sizes and stand treatments. Models were estimated using a linear mixed-effects procedure to account for within-stand correlations. The functions for biomass and BEFs included only diameter at breast height and total tree height for individual trees as predictor variables. Inclusion of additional variables reflecting site quality or stand density did not improve model performance. The functions for basic density included individual tree diameter, tree height and quadratic mean diameter as predictor variables, indicating an effect of stand density on the basic density of wood and bark.
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| 17. |
- Skovsgaard, Jens Peter
(författare)
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Bog om naturnær skovdrift
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 505-505
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Book review: "G.J. Wilhelm & H. Rieger 2013: Naturnahe Waldwirtschaft mit der QD-Strategi. Ulmer."
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| 18. |
- Skovsgaard, Jens Peter
(författare)
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Bog om skovdyrkning
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 505-505
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Book review: "P. Savill 2013: The silviculture of trees used in British forestry. CABI."
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| 19. |
- Skovsgaard, Jens Peter
(författare)
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Bog om tarmvridrøn
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 551-551
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Book review N. Mayer & R.T. Klumpp (ed.) 2013: Elsbeere in Österreich – Monographie. Verein zur Erhaltung, Pflege und Vermarktung der Elsbeere - Genussregion Wiesenwienerwald Elsbeere, Michelbach.
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| 20. |
- Skovsgaard, Jens Peter
(författare)
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Crown structure, growth, and drought tolerance of true service tree (Sorbus domestica L.) in forests and urban environments
- 2024
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Ingår i: Urban Forestry and Urban Greening. - 1618-8667 .- 1610-8167. ; 91
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Tidskriftsartikel (refereegranskat)abstract
- True service tree (Sorbus domestica L.) is a rare native species of Central Europe. It grows well in dry and warm environments and may consequently be well adapted to the expected future climate further north. It is considered a potentially suitable species for climate change adaptation in forests and urban environments. In this study, we used total tree height, stem diameter, and crown dimensions of true service trees in Germany, southern Scandinavia, northern Italy, and Slovakia to determine the species' allometric relationships and space re-quirements. Additionally, we used tree cores from Germany and Slovakia and stem discs of a true service tree in Copenhagen to study growth patterns and drought stress response. Throughout, we compared to oak (Quercus robur L. and Quercus petraea (Matt.) Liebl.), as common and well-studied species. Our results indicated that true service tree and the two oak species have similar growth patterns and space requirements. True service tree and oak both had a fast growth in their youth, followed by a gradual reduction at later stages. The crown projection area of true service tree was similarly influenced by competitors as that of oak, indicating a similar sensitivity towards competition. Likewise, we identified similarities in growth response to drought and, hence, drought tolerance. Due to their comparable growth pattern and drought tolerance, we hypothesise that oak, in many regards, can be used as a model species for the management of true service tree.
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| 21. |
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| 22. |
- Skovsgaard, Jens Peter
(författare)
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Den rekreative værdi af udrensning i eg : Mener professionelle skov- og naturforvaltere, det samme som befolkningen?
- 2014
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Ingår i: Skoven. - 0106-8539. ; 1, s. 16-19
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Den danske befolkning foretrækker ung egeskov uden kvas i skovbunden, så det er let at gå mellem træerne. Forstfolk og landskabsarkitekter er ligeglade med, om der er kvas. Befolkningen synes bedst om tæt, men tyndet skov med et lukket kronetag. Det gør professionelle forstfolk også, men landskabsarkitekter foretrækker fritstående træer fremfor sluttede bevoksninger.
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| 23. |
- Skovsgaard, Jens Peter, et al.
(författare)
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Ecology and silviculture of SPRUCE
- 2011
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 26, s. 1-2
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Various species of spruce comprise a significant part of forests in the northern hemisphere and are widely used in forest management. The management of spruce influences carbon sequestration and the production of biomass that can be used as a substitute for fossil fuels. In addition, climate change may affect future management practices. Site requirements for certain species may shift, and new potential risks may have to be considered when designing future management programs. During 31 August-3 September 2009, the Faculty of Forestry at the Swedish University of Agricultural Sciences (SLU) hosted an international conference on SPRUCE IN THE CONTEXT OF GLOBAL CHANGE in Halmstad, Sweden. The conference was organized under the auspices of IUFRO Working Party 1.01.08 “Ecology and Silviculture of Spruce”. The conference included 50 high-quality scientific presentations, 12 of which were invited to submit their contribution to this special issue of Scandinavian Journal of Forest Research. The papers were peer-reviewed by a panel of internationally renowned scientists, and this process resulted in a total of eight printed papers. Focusing on a diverse range of topics, we believe that these papers represent an interesting and timely sample of spruce research that will be of interest to the international community of forest scientists and even to forest policymakers and forest managers. The full proceedings are available from the conference homepage at http://www-spruce2009.slu.se
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| 24. |
- Skovsgaard, Jens Peter
(författare)
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Effects of Norway spruce shelter density and soil scarification method on mortality and height growth of underplanted European beech, European silver fir and Douglas fir
- 2023
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Ingår i: Forestry. - : Oxford University Press (OUP). - 0015-752X .- 1464-3626. ; 96, s. 481-497
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Tidskriftsartikel (refereegranskat)abstract
- In Europe, 6-7 million ha even-aged, pure stands of Norway spruce grown outside its natural range are prone to butt rot, windthrow, and bark beetle infestation. Climate change may well accelerate these problems and there is an urgent need to develop methods for converting Norway spruce plantations into more heterogeneous forest with larger resistance and resilience towards natural disturbances. Based on a field experiment located on former heathland on an outwash plain in western Denmark, we examined the mortality and height growth of European beech (Fagus sylvatica L.), European silver fir (Abies alba Mill.), and Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) planted under a shelterwood of 17-19 m tall Norway spruce (Picea abies (L.) Karst.) at shelter densities initially ranging by basal area from 10 to 36 m(2) ha(-1) (271-1099 stems ha(-1)). Underplanting included plots of beech (100 per cent) and silver fir (100 per cent) as well as plots with two-species mixtures of silver fir/beech (66 per cent/33 per cent and 33 per cent/66 per cent) and Douglas fir/beech (66 per cent/33 per cent). The experiment also included two soil scarification methods (patch and strip scarification). The experiment was laid out in an unbalanced factorial split-plot design, replicated in time and space, and totaling 144 plots in four blocks. The experiment was followed for 19 years during which a gradual reduction in shelter density took place although in some plots the shelterwood was removed abruptly by windthrow and bark beetle infestation. Shelter densities larger than 10 m(2) ha(-1) had only a minor effect on the mortality of beech and silver fir, while shelter densities larger than 20 m(2) ha(-1) resulted in increased mortality of Douglas fir. Subsequent abrupt reduction in shelter density resulted in increased mortality, especially of silver fir. Height growth decreased with increasing shelter density, more for Douglas fir than for beech, and marginally more for beech than for silver fir. For shelter densities <15 m(2) ha(-1), height growth of silver fir was unaffected. Beech grew faster when mixed with Douglas fir. The soil scarification method did not influence mortality, but strip scarification resulted in marginally larger height growth than patch scarification. We hypothesize that the shelter effect was related mainly to competition for light, while late frost and browsing were important factors in open shelters (<10 m(2) ha(-1)). Based on these results, recommended initial shelter densities are at or <10 m(2) ha(-1) for the establishment of Douglas fir, at similar to 15-20 m(2) ha(-1) for silver fir, and around 15 m(2) ha(-1) for beech.
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| 25. |
- Skovsgaard, Jens Peter, et al.
(författare)
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Effects of Thinning Practice, High Pruning and Slash Management on Crop Tree and Stand Growth in Young Even-Aged Stands of Planted Silver Birch (Betula pendula Roth)
- 2021
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Ingår i: Forests. - : MDPI AG. - 1999-4907. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- The objective was to quantify the influence of thinning, high pruning and slash management on crop tree and stand growth in young even-aged stands of planted silver birch (Betula pendula Roth). This study was based on two field experiments, aged six and eleven years at initiation and re-measured after six and eight years, respectively. Treatments included the unthinned control, moderate thinning mainly from below (removing 28-33% of standing volume), point thinning to favor 300 trees per ha and with no thinning elsewhere in the plot (removing 16-25%), and heavy thinning leaving 600 evenly distributed potential future crop trees per ha (removing 64-75%). Slash management (extraction or retention) was applied to heavily thinned plots. High pruning removing 30-70% of the green crown was carried out in some plots with point or heavy thinning on 300 or 600 trees per ha, respectively. Stand volume growth increased with increasing pre-treatment mean annual volume increment and decreased with increasing thinning intensity as compared to the unthinned control. LS-means estimates indicated a reduction for moderate thinning by 14%, for point thinning by 12% and for heavy thinning (combined with pruning) by 62%. However, in the youngest experiment, heavy thinning (without pruning) reduced growth by 54%. Combining these results with results from a similar experiment in Canada, the reduction in stand volume growth (Red(Iv%)) depending on thinning removal (Rem(V%)), both expressed as a percentage of the unthinned control, was quantified as Red(Iv%) = -23.67 + 1.16 center dot Rem(V%) (calibration range: 30-83%). For heavy thinning (large quantities of slash), slash extraction resulted in no reduction in stand volume growth as compared to slash retention. The instantaneous numeric reduction in the average stem diameter of the 300 thickest trees per ha (D-300) due to thinning was 3.5, 15-21% and 955-11% with moderate, point and heavy thinning, respectively. The subsequent average annual increase in D-300 during the observation period was 8.5%, 25 and 18%, respectively. In the youngest experiment, pruning in unthinned plots led to a reduction in the annual increase of D-300 by 14%, and heavy thinning in unpruned plots led to an increase by 30%. The growth of pre-selected potential future crop trees increased with increasing thinning intensity. In heavily thinned plots, pruning reduced growth increasingly with increasing pruning severity; LS-means estimates indicated 21% larger growth on stem diameter for unpruned trees and 3% for pruned trees. As an adverse side effect, heavily thinned plots with only 600 trees per ha were at increased risk of windthrow for some years after the thinning intervention. In the oldest experiment, 95-21% of the trees in these plots were damaged by wind.
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| 26. |
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| 27. |
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| 28. |
- Skovsgaard, Jens Peter
(författare)
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Forest site productivity: a review of spatial and temporal variability in natural site conditions
- 2013
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Ingår i: Forestry. - : Oxford University Press (OUP). - 0015-752X .- 1464-3626. ; 86, s. 305-315
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Forskningsöversikt (refereegranskat)abstract
- Indicators of forest site productivity may exhibit considerable spatial and temporal variability that should be considered in sustainable forest management. It is generally assumed that natural site conditions and, in turn, site productivity changes gradually and predictably. Our review illustrates many exceptions to this paradigm. Consequently, uni-dimensional productivity indicators such as the commonly used site index (estimated based on stand height) is not always sufficient to characterize site productivity for apparently homogeneous forest stands. To alleviate this problem, we suggest a hierarchical procedure for the estimation of forest site productivity including site mapping, unthinned reference stands (against which to measure growth performance) and adaptive modelling. The level and detail at which site mapping should be conducted (region, forest, management unit or subunit), depends on the objective (research vs. operational forestry), forest type and expected deviations in site productivity estimates compared with the cost of site mapping. Unthinned reference plots should preferably be maintained in the long term and the number of plots should increase with increasing site or stand heterogeneity (for homogeneous land we recommend one plot in 10 ha, two in 100 ha, etc.). With adaptive modelling site specific parameters can be updated at any time when new information has become available. Finally, the review indicates a need to re-define traditional measurement procedures to achieve a contemporary and rational statistical basis for the estimation of site productivity.
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| 29. |
- Skovsgaard, Jens Peter
(författare)
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Functions for biomass and basic density of stem, crown and root system of Norway spruce (Picea abies (L.) Karst.) in Denmark
- 2011
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 26, s. 3-20
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Tidskriftsartikel (refereegranskat)abstract
- Models for predicting the biomass of forest trees are becoming increasingly important for assessing forest resources and carbon sequestration in forests. We developed functions for predicting the biomass and basic density of above- and below-ground parts of Norway spruce (Picea abies (L.) Karst.) in Denmark. Separate models were developed for branches (including foliage), stem and the below-ground stump and root system as well as for the aggregate components of total above-ground biomass and total tree biomass. Trees were sampled in 14 forest stands, reflecting the range of growth conditions and thinning practises of Norway spruce in Denmark. Because of inclusion of experimental plots, data reflected a wider range of thinning practices than commonly used in forestry practice. The data included measurements of biomass and basic density from 114 trees, two of which were regarded as outliers and consequently excluded in the final model estimation. The final models reflected known properties of tree growth and allocation of biomass among different tree components of even-aged Norway spruce. The models were successful in predicting biomass, basic density and biomass expansion factors across a wide variety of tree sizes, stand treatments and growth conditions. The models are believed to substantially improve national estimates of carbon sequestration and biomass resources.
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| 30. |
- Skovsgaard, Jens Peter, et al.
(författare)
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High-pruning of European beech (Fagus sylvatica L.) and pedunculate oak (Quercus robur L.): work efficiency for target pruning as a function of tree species, pruning height, branch characteristics, pole saw type and operator
- 2018
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 33, s. 511-517
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to establish an operational model of productive work time per tree (work efficiency) for high-pruning of young European beech and pedunculate oak depending on tree species, pruning height, branch characteristics, pole saw type and operator. The final model included all of these independent variables with branch characteristics specified in terms of number of live branches and cross-sectional area of the thickest branch at the cut. Work time increased with increasing values of each of the three numeric variables. For a given pruning height the size of the largest branch was for all practical purposes more influential than the number of live branches. Beech took 28% longer to prune than oak. The German Ergo-Schnitt saw was 21% slower than the Japanese Silky Hayauchi saw. The variation in worker performance within our study was larger than that attributed to tree species and pruning equipment.
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| 31. |
- Skovsgaard, Jens Peter, et al.
(författare)
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High-pruning of silver birch (Betula pendula Roth): work efficiency as a function of pruning method, pole saw type, slash removal, operator, pruning height and branch characteristics
- 2018
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Ingår i: International Journal of Forest Engineering. - : Informa UK Limited. - 1494-2119 .- 1913-2220. ; 29, s. 117-127
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to establish an operational model of work efficiency (net or productive work time per tree) for high-pruning of young silver birch depending on pruning method, pole saw type, operator, pruning height and branch characteristics. The final model included number of branches, cross-sectional area of the thickest branch at the cut, pruning height, pruning method (target or flush pruning) and operator as independent variables. Work time increased with increasing values of each of the three numeric variables. For a given pruning height the number of branches was for all practical purposes more influential than the size of the largest branch. Target pruning was significantly faster than flush pruning, all else being equal. The variation in work efficiency for the five operators in the study spanned a range almost twice as large as that attributed to pruning method. The mean work time for other activities during the pruning operation (supportive work time) was estimated at 17% of the productive work time for pruning.
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| 32. |
- Skovsgaard, Jens Peter
(författare)
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Hvad er asketoptørre?
- 2011
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Ingår i: Skovdyrkeren. ; , s. 5-6
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 33. |
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| 34. |
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| 35. |
- Skovsgaard, Jens Peter
(författare)
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Models for supporting forest management in a changing environment
- 2010
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Ingår i: Agroforestry Systems. - 0167-4366 .- 1572-9680. ; 19, s. 8-29
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Tidskriftsartikel (refereegranskat)abstract
- Forests are experiencing an environment that changes much faster than during the past several hundred years. In addition, the abiotic factors determining forest dynamics vary depending on its location. Forest modeling thus faces the new challenge of supporting forest management in the context of environmental change. This review focuses on three types of models that are used in forest management: empirical (EM), process-based (PBM) and hybrid models. Recent approaches may lead to the applicability of empirical models under changing environmental conditions, such as (i) the dynamic state-space approach, or (ii) the development of productivity-environment relationships. Twenty-five process-based models in use in Europe were analyzed in terms of their structure, inputs and outputs having in mind a forest management perspective. Two paths for hybrid modeling were distinguished: (i) coupling of EMs and PBMs by developing signal-transfer environment-productivity functions; (ii) hybrid models with causal structure including both empirical and mechanistic components. Several gaps of knowledge were identified for the three types of models reviewed.The strengths and weaknesses of the three model types differ and all are likely to remain in use. There is a trade-off between how little data the models need for calibration and simulation purposes, and the variety of input-output relationships that they can quantify. PBMs are the most versatile, with a wide range of environmental conditions and output variables they can account for. However, PBMs require more data making them less applicable whenever data for calibration are scarce. EMs, on the other hand, are easier to run as they require much less prior information, but the aggregated representation of environmental effects makes them less reliable in the context of environmental changes. The different disadvantages of PBMs and EMs suggest that hybrid models may be a good compromise, but a more extensive testing of these models in practice is required.
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| 36. |
- Skovsgaard, Jens Peter
(författare)
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Monografier over træer
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 551-551
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Book review: " A. Parciak, 9 co-editors og 118 contributors, 2013: The CABI Encyclopedia of Forest Trees. CABI."
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| 37. |
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| 38. |
- Skovsgaard, Jens Peter
(författare)
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Planting Wild Service Trees : Some practical advice
- 2014
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Ingår i: Quarterly Journal of Forestry. - 0033-5568. ; 108, s. 188-191
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- In this article we briefly summarize ecological and silvicultural characteristics of wild service tree (Sorbus torminalis (L.) Crantz) and, based on personal experience, offer practical advice for forest management. Our main focus is silviculture for timber production. We specifically address site properties (soil type and exposure), nursery stock issues (plant type and genetic origin), abiotic and biotic production risks (frost, wind, browsing and rubbing), establishment practices (herbicides, fencing and tree shelters), pruning (formative and high pruning) and (early) growth performance. We also briefly address intangible values associated with wild service tree such as biodiversity enrichment and landscape aesthetics. Finally, we encourage more planting of wild service tree and the conscious application of suitable silvicultural practices.
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| 39. |
- Skovsgaard, Jens Peter
(författare)
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Pre-commercial thinning in naturally regenerated stands of European beech (Fagus sylvatica L.): effects of thinning pattern, stand density and pruning on tree growth and stem quality
- 2019
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Ingår i: Forestry. - : Oxford University Press (OUP). - 0015-752X .- 1464-3626. ; 92, s. 120-132
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Tidskriftsartikel (refereegranskat)abstract
- Pre-commercial thinning in naturally regenerated stands of European beech is often expensive and must be justified by improved development of the remaining crop. Based on a field experiment established in two 14-year-old naturally regenerated beech stands in Denmark, we investigated some effects of pre-commercial thinning and pruning on future crop tree growth and stem quality. The treatments included (1) no thinning, (2) moderate to heavy strip thinning, with or without subsequent selective thinning, and (3) extremely heavy strip thinning in two perpendicular directions (checkerboard thinning), with or without subsequent selective thinning and with or without pruning. The resulting residual stand densities ranged from 10(5) to only 200 ha(-1). Treatment effects were evaluated on one potential future crop tree for every 100 m(2). Potential future crop trees were selected 32 years after germination based on spatial distribution, growth potential and stem quality. Total crop tree height was unaffected by strip thinning, but reduced by checkerboard thinning. Stem diameter at 1.30 m above ground level increased with decreasing stand density but, for checkerboard thinning, was reduced by pruning. The lower live branch was located at a lower position with heavy strip thinning and with checkerboard thinning without pruning. The frequency of crop trees with a forked stem was largest with checkerboard thinning and these forks were located at a lower position. Stem tilt and stem bend (stem straightness) were essentially unaffected by thinning practice. However, pruned trees tilted less and had straighter stems. The initial formation of epicormic branches on crop trees was unrelated to thinning and pruning practice, but crop trees that had been pruned for these were less prone to subsequently develop epicormic branches. In summary, moderate to heavy pre-commercial thinning had no effect on stem quality, while extremely heavy thinning without pruning resulted in unacceptably low stem quality. The no-thinning option resulted in acceptable growth and stem quality of the crop trees and this remains a viable management alternative for young beech.
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| 40. |
- Skovsgaard, Jens Peter
(författare)
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Recreational preferences depending on thinning practice in young even-aged stands of pedunculate oak (Quercus robur L.): comparing the opinions of forest and landscape experts and the general population of Denmark
- 2013
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 28, s. 668-676
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate to which extent forestry professionals, other green professionals (mainly landscape architects) and natural resource students in Denmark agree with the general population regarding their recreational preferences for contrasting stem densities in young, even-aged stands of pedunculate oak (Quercus robur L.). The study was based on five pairs of colour photographs from each of the five recently thinned experimental plots in a 13-year-old stand. The plots represented five different residual stem densities: 7000 (unthinned), 5300 (traditional thinning), 1000, 300 and 100 stems ha(-1). All cut trees were left on the ground. The analysis was carried out as a survey of forest and landscape experts (n=158) and the general public (n=243) based on questionnaires. Interviewees ranked the photographs according to the criterion: Which forest environment do you prefer as a visitor? Principal component factor analysis showed that the general public tended to perceptually group photos according to similar overall pattern of openness, presence of row structure and stand accessibility (including presence/absence of slash). As long as a stand appeared accessible, stand density had little influence on their preferences for a wide range of stand densities (5300-300 stems ha(-1)). In contrast, foresters, other green professionals and students seemed to perceptually group photos according to treatment type, and the presence of slash had little influence on their preferences. This suggests an influence of professional background, making experts visually analyse and evaluate stands according to contemporary management standards and paradigms within their own profession.
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| 41. |
- Skovsgaard, Jens Peter
(författare)
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Røn på Bornholm: en botanisk og forvaltningsmæssig udfordring
- 2013
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Ingår i: Dansk dendrologisk årsskrift. - 0416-6906. ; 30, s. 6-25
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Der er fem naturligt forekommende rønnearter på Bornholm: almindelig røn, finsk røn, seljerøn, klipperøn og tarmvridrøn. Formålet med denne artikel er at gøre opmærksom på røns potentiale som skovtræ og på de udfordringer, der er med at forvalte den bornholmske genressource i røn. Der er røn overalt på Bornholm, på vanskeligt tilgængelige klipper langs kysten, ude i det åbne land og inde i skoven. Almindelig røn forekommer i næsten alle habitattyper på øen. Finsk røn, som er den sjældneste art, findes mest i klippeområder og kratskov. Seljerøn ses næsten udelukkende i det åbne land, hvor den ofte er plantet. Klipperøn er en udkantsart, som kun findes på skrænter og i klippeterræn. Tarmvridrøn forekommer både på eksponerede klipper, i krat og inde i skoven. Bortset fra almindelig røn er der ofte kun få individer i hver population, og populationerne er ofte adskilte uden umiddelbar biologisk forbindelse. Der tale om en vigtig genressource, både nationalt og internationalt. Røn på Bornholm kræver derfor særlig opmærksomhed i skovdriften og ved anden naturforvaltning. Tarmvridrøn og seljerøn har umiddelbart potentiale til skovdyrkning. Det skyldes især deres vækstpotentiale og muligheden for at opnå en for røn forholdsvis høj alder. Også almindelig røn, finsk røn og måske klipperøn kan under de rette omstændigheder være egnede til skovdyrkning.
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| 42. |
- Skovsgaard, Jens Peter
(författare)
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Røn på Bornholm: en genetisk smeltedigel for tarmvridrøn, klipperøn, seljerøn, finsk røn og almindelig røn.
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 296-299
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Bornholm is a Danish island located in the Baltic Sea between Sweden and Poland. The island covers an area of 588 km2. The soils are derived mainly from Holocene glacial till overlying Pre-cambric gneiss or granite and, at some places, Cambro-Silurian sandstone or shale. There are frequent outcrops of bedrock. There are five Sorbus species on Bornholm (Figure 2): wild service tree (Sorbus torminalis ( L.) Crantz), rock whitebeam (Sorbus rupicola (Syme) Hedl.), Swedish whitebeam (Sorbus intermedia (Ehrh.) Pers.), Swedish service tree (Sorbus hybrida L.), and rowan (Sorbus aucuparia L.) The botanical, genetic and ecological characteristics of each Sorbus species are briefly outlined. It is argued that wild service tree, Swedish whitebeam and rowan could play a larger role in silviculture. Rock whitebeam (due to its bushy growth) and Swedish service tree (due to its infrequent occurrence) are considered of little or no interest for silviculture. Wild service tree: A large share of Denmark's natural populations of wild service tree is found on Bornholm, primarily on inaccessible coastal cliffs, but also in the forest. On coastal cliffs wild service tree often only grows to the size of a bush or a small tree (Figure 1), while in the forest it can grow to timber dimensions (Figure 3). Although there are only few individuals in each population, they collectively represent an important genetic resource. It is suggested to establish a seed orchard based on locally collected scions and to install experiments comparing controlled-pollination offspring to offspring from, for example, the large autochthonous population in Ulvshale Forest on the Danish island of Møn or the superior German populations at Sailershausen. Swedish whitebeam: Swedish whitebeam is found almost exclusively in the open landscape, where it is frequently planted in hedgerows and as a solitary tree. It thrives particularly well on calcareous sites, but clearly has a much wider site potential (as witnessed by its growth when planted on other site types in northern Europe). Swedish whitebeam is healthy and wind firm, tolerates salt-spray deposition and is capable of producing a sizeable stem of timber quality (Figure 4). Due to the species' asexual reproduction through agamospermy or apomixis, offspring will inherit essential mother tree characteristics such as growth potential, stem form and health status. It is suggested that Swedish whitebeam should be tested for forestry use. Rowan: Rowan is one of the commonest tree species in many parts of Europe, including Bornholm. It is not dealt with specifically in this article, but it is suggested that the species should be considered given a more prominent role in forestry. Finally, it is pointed out that Bornholm deserves more attention in Sorbus research. The island's role as a genetic melting pot for Sorbus at species and genus level has not yet been explored. Due to its geographic isolation from other Sorbus populations Bornholm could be an interesting case-study, not only for research, but also for the development and testing of suitable management practices for conservation as well as for economic forestry.
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| 43. |
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| 44. |
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| 45. |
- Skovsgaard, Jens Peter, et al.
(författare)
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Silvicultural strategies for Fraxinus excelsior in response to dieback caused by Hymenoscyphus fraxineus
- 2017
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Ingår i: Forestry. - : Oxford University Press (OUP). - 0015-752X .- 1464-3626. ; 90, s. 455-472
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Forskningsöversikt (refereegranskat)abstract
- Ash dieback caused by the invasive alien fungal pathogen Hymenoscyphus fraxineus often has devastating consequences for the survival, growth and wood quality of Fraxinus excelsior. We analyse the silvicultural implications of ash dieback in forest stands in Europe and review the advice on how to modify management accordingly. We draw on literature as well as unpublished observations and personal experience. The relevant strategy depends on the management objective, the site type (moist or dry), the stand type (pure or mixed stands, even-aged or uneven-aged stands), the age and the degree of dieback. Generally, the strategy should be conservative and trees that are healthy or slightly damaged may be marked and retained. Where dieback is severe, the suggested approach is to harvest remaining commercial timber before value depreciation and to regenerate or replant the area with other tree species. In forests of high value for habitat conservation, it may be advisable to let natural succession proceed unhindered. In all situations, forestry practice plays a key role in implementing in situ and ex situ conservation strategies for ash by preserving trees with low damage levels in all phases of stand development. Wherever there are infected ash trees, risks for operational staff, forest visitors and infrastructure posed by damaged, destabilized ash trees must be minimized.
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| 46. |
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| 47. |
- Skovsgaard, Jens Peter
(författare)
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Simultaneous estimation of biomass models for 13 tree species: effects of compatible additivity requirements
- 2017
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Ingår i: Canadian Journal of Forest Research. - : Canadian Science Publishing. - 0045-5067 .- 1208-6037. ; 47, s. 765-776
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Tidskriftsartikel (refereegranskat)abstract
- A desirable feature of biomass models distinguishing different tree components is compatible additivity of the component functions. Due to forcing of parameter estimates, such additivity is achieved at an expense of precision of the component functions. This study aimed to analyse the loss of precision incurred by forcing of parameters in tree biomass models due to (i) additivity constraints, (ii) combining global and species-specific parameters, and (iii) estimating component functions simultaneously as a system instead of as individual equations. Based on biomass data from 697 trees including 13 different species, we estimated a set of compatibly additive, nonlinear biomass models using simultaneous estimation and compared these with less restricted model systems. In line with other similar studies, the overall model system explained 88%-99% of the variation in individual biomass components. Compared with the unrestricted model, restricting parameters to obtain compatible additivity resulted in a change in RMSE of -0.6% to 5.4%. When restricting parameter estimates using both species-specific and global parameters, RMSE increased by 1.7%-13.1%. Estimating model parameters using simultaneous estimation (nonlinear iterated seemingly unrelated regression, NSUR) increased model bias compared with ordinary least squares estimation (OLS) for most biomass components. Contrary to expectations, NSUR estimation did not lead to a reduction in the standard error of estimates.
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| 48. |
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| 49. |
- Skovsgaard, Jens Peter
(författare)
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Store tarmvridrøn 2 : Et træ i Vemmetofte er Danmarks tredjestørste
- 2015
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Ingår i: Skoven. - 0106-8539. ; 47, s. 534-535
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Danmarks tredjestørste tarmvridrøn står i Vemmetofte på Østsjælland. Det spektakulære træ har to stammer med en diameter på henholdsvis 49 og 53 cm i brysthøjde, højden er 17 m. Træets alder og oprindelse er ukendt.
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| 50. |
- Skovsgaard, Jens Peter
(författare)
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Store tarmvridrøn. Verdens tykkeste tarmvridrøn står i Danmark
- 2013
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Ingår i: Skoven. - 0106-8539. ; 45, s. 451-455
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- The thickest wild service tree in the world The world's thickest wild service tree is located in Moesgaard Park south of Aarhus, Denmark (Figure 1). In 2013 the stem diameter at breast height (dbh) was 148 cm (circumference = 464 cm) and total tree height was 24 m. The stem forks at a height of 2 m above ground, but this does not influence the stem diameter at 1.30 m. The crown diameter was between 21.6 and 26.4 m. The health condition of the tree was excellent, but with some top dieback. The origin and age of the tree remain unknown, but based on archival studies and growth estimates derived from past measurements of stem diameter (Table 1) we believe it was planted sometime between 1783 and 1808, resulting in an estimated age of between 205 and 230 years. In 2009 we collected fruits, extracted seeds (1.53 seeds per fruit, average weight = 0.03775 g per seed) and had them sown. Germination was successful, but the seedlings appeared to originate from hybridization (based on poor growth and odd foliage) and most of them eventually died. The second thickest wild service tree in Denmark The second thickest wild service tree in Denmark is located in the Arboretum at Charlottenlund north of Copenhagen (Figure 2). The tree originates from the Mediterranean region and was planted in 1851. In 2013, at an age of 162-165 years, dbh was 82 cm, height was almost 22 m and the tree was still in good health. The stem has had an average growth rate of 1.56-1.59 cm per year on circumference, or 0.5 cm per year on dbh. Large wild service trees in the forest The largest wild service trees in the forests of Denmark can be found in Døndalen Forest on the island of Bornholm (Skoven 2013/6-7) and in Ulvshale Forest on the island of Møn (Skoven 2013/1). Both locations host trees with a dbh up to 36 cm and a height up to 17.5 m (one tree has been measured at over 20 m). Elsewhere in Europe wild service tree in forest settings may reach stem diameters of more than 70 cm (Figure 3). Based on past measurements the growth rate of the largest wild service trees in the unmanaged Ulvshale Forest was estimated at 1.8-4.4 mm per year during 2002-12. Large wild service trees in other countries A wild service tree on Parsonage Farm 15 km northeast of Hastings in Great Britain and one at Thenneberg 45 km southwest of Vienna in Austria had stem diameters similar to that of the large tree at Moesgaard in Denmark, but both collapsed some years ago. A wild service tree in a field near Mayerling 35 km southwest of Vienna is now believed to be the second thickest in the world, with a dbh of approximately 15 cm less than that of the Moesgaard tree. Below this are a number of trees with stem diameters of 100-120 cm, many of which are located in Austria (Figure 4). Conclusion The large wild service tree in Moesgaard Park has been known for decades as one of the thickest in the world and now is clearly the outright champion. The tree at Charlottenlund is probably the second thickest in Denmark. The ages of the trees as well as their growth performance and good health indicate the potential of wild service tree in Denmark and that the species is suited for use in silviculture. The growth rates indicate that a target dbh of 50 cm is suitable for silviculture in Denmark.
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