TY - JOUR A1 - Feichtinger, Linda M. A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Rigling, Andreas T1 - Growth adjustments of conifers to drought and to century-long irrigation JF - Forest Ecology and Management N2 - Our knowledge on tree responses to drought is mainly based on short-term manipulation experiments which do not capture any possible long-term adjustments in this response. Therefore, historical water channels in inner-Alpine dry valleys were used as century-long irrigation experiments to investigate adjustments in tree growth to contrasting water supply. This involved quantifying the tree-ring growth of irrigated and non-irrigated (control) Scots pine (Pinus sylvestris L.) in Valais (Switzerland), as well as European larch (Larix decidua Mill.) and black pine (Pinus nigra Arnold) in Vinschgau (Italy). Furthermore, the adjustments in radial growth of Scots pine and European larch to an abrupt stop in irrigation were analyzed. Irrigation promoted the radial growth of all tree species investigated compared to the control: (1) directly through increased soil water availability, and (2) indirectly through increased soil nutrients and humus contents in the irrigated plots. Irrigation led to a full elimination of growth responses to climate for European larch and black pine, but not for Scots pine, which might become more sensitive to drought with increasing tree size in Valais. For the control trees, the response of the latewood increment to water availability in July/August has decreased in recent decades for all species, but increased in May for Scots pine only. The sudden irrigation stop caused a drop in radial growth to a lower level for Scots pine or similar level for larch compared to the control for up to ten years. However, both tree species were then able to adjust to the new conditions and subsequently grew with similar (Scots pine) or even higher growth rates (larch) than the control. To estimate the impact of climate change on future forest development, the duration of manipulation experiments should be on longer time scales in order to capture adjustment processes and feedback mechanisms of forest ecosystems. Y1 - 2014 U6 - http://dx.doi.org/10.1016/j.foreco.2014.08.008 SN - 1872-7042 (Online) SN - 0378-1127 (Print) VL - 2014 IS - 334 SP - 96 EP - 105 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Weemstra, Monique A1 - Eilmann, Britta A1 - Sass-Klaassen, Ute G. W. A1 - Sterck, Frank J. T1 - Summer droughts limit tree growth across 10 temperate species on a productive forest site JF - Forest Ecology and Management Y1 - 2013 U6 - http://dx.doi.org/doi:10.1016/j.foreco.2013.06.007 SN - 0378-1127 (Print) SN - 1872-7042 (Online) VL - 2013 IS - 306 SP - 142 EP - 149 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Eilmann, Britta A1 - de Vries, Sven M. G. A1 - den Ouden, Jan A1 - Mohren, Godefridus M. J. A1 - Sauren, Pascal A1 - Sass-Klaassen, Ute G. W. T1 - Origin matters! Difference in drought tolerance and productivity of coastal Douglas-fir (Pseudotsuga menziesii (Mirb.)) provenances JF - Forest Ecology and Management Y1 - 2013 U6 - http://dx.doi.org/doi:10.1016/j.foreco.2013.03.031 SN - 1872-7042 (Online) SN - 0378-1127 (Print) VL - 2013 IS - 302 SP - 133 EP - 143 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Eilmann, Britta A1 - Sterck, Frank J. A1 - Wegner, L. A1 - de Vries, Sven M. G. A1 - von Arx, G. A1 - Mohren, Godefridus M. J. A1 - den Ouden, Jan A1 - Sass-Klaassen, Ute G. W. T1 - Wood structural differences between northern and southern beech provenances growing at a moderate site JF - Tree Physiology Y1 - 2014 U6 - http://dx.doi.org/10.1093/treephys/tpu069 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 34 IS - 8 SP - 882 EP - 893 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Rigling, Andreas ED - Abrams, Marc T1 - Tree-growth analyses to estimate tree species' drought tolerance JF - Tree Physiology N2 - Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species. Y1 - 2012 U6 - http://dx.doi.org/10.1093/treephys/tps004 SN - 0829-318X (Print) SN - 1758-4469 (Online) VL - 32 IS - 2 SP - 178 EP - 187 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Wegner, Lena A1 - von Arx, Georg A1 - Sass-Klaassen, Ute G. W. A1 - Eilmann, Britta T1 - ROXAS – an efficient and accurate tool to detect vessels in diffuse-porous species JF - IAWA Journal / International Association of Wood Anatomists Y1 - 2013 U6 - http://dx.doi.org/10.1163/22941932-00000034 SN - 0928-1541 (Print) SN - 2294-1932 (Online) VL - 34 IS - 4 SP - 425 EP - 432 PB - Brill CY - Leiden ER - TY - JOUR A1 - Eilmann, Britta A1 - Zweifel, Roman A1 - Buchmann, Nina A1 - Graf Pannatier, Elisabeth A1 - Rigling, Andreas T1 - Drought alters timing, quantity, and quality of wood formation in Scots pine JF - Journal of Experimental Botany Y1 - 2011 U6 - http://dx.doi.org/10.1093/jxb/erq443 SN - 1460-2431 (Online) SN - 0022-0957 (Print) VL - 62 IS - 8 SP - 2763 EP - 2771 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Fonti, Patrick A1 - Eilmann, Britta A1 - García-González, Ignacio A1 - von Arx, Georg T1 - Expeditious building of ring-porous earlywood vessel chronologies without loosing signal information JF - Trees : structure and function Y1 - 2009 U6 - http://dx.doi.org/10.1007/s00468-008-0310-z SN - 0931-1890 (Print) SN - 1432-2285 (Online) VL - 23 IS - 3 SP - 665 EP - 671 PB - Springer CY - Berlin ER - TY - JOUR A1 - Eilmann, Britta A1 - Weber, Pascale A1 - Rigling, Andreas A1 - Eckstein, Dieter T1 - Growth reactions of Pinus sylvestris L. and Quercus pubescens Willd. to drought years at a xeric site in Valais, Switzerland JF - Dendrochronologia Y1 - 2006 U6 - http://dx.doi.org/doi:10.1016/j.dendro.2005.10.002 SN - 1612-0051 (Online) SN - 1125-7865 (Print) VL - 23 IS - 3 SP - 121 EP - 132 ER - TY - JOUR A1 - Rigling, Andreas A1 - Elkin, Ché A1 - Dobbertin, Matthias A1 - Eilmann, Britta A1 - Giuggiola, Arnaud A1 - Wohlgemuth, Thomas A1 - Bugmann, Harald T1 - Wald und Klimawandel in der inneralpinen Trockenregion Visp JF - Schweizerische Zeitschrift für Forstwesen N2 - Der Temperaturanstieg der vergangenen Jahrzehnte war in Gebirgsregionen besonders ausgeprägt. Sollte sich dieser Temperaturtrend im 21. Jahrhundert fortsetzen, dann dürf-ten sich auch die Häufigkeit und Intensität von Niederschlä-gen und Trockenperioden verändern, was die Waldwirtschaft vor grosse Herausforderungen stellen wird. Trockenheit ist ein entscheidender Faktor für die Waldökosysteme der inner-alpinen Täler, wo seit Jahren trockenheitsbedingtes Baum-sterben festgestellt wird. Der vorliegende Beitrag hat zum Ziel, die Sensitivität der verschiedenen Waldökosysteme ge-genüber Klimawandel und alternative, teilweise extreme Bewirtschaftungsvarianten in der Region Visp zu testen. Me-thodische Ansätze wie Monitoring, Feldexperimente und dy-namische Modellierung wurden kombiniert, und es wurden verschiedene Ökosystemleistungen berücksichtigt, so Holz-produktion, Schutz vor Naturgefahren, Kohlenstoffspeiche-rung und Aspekte der Biodiversität. Die Resultate deuten da-rauf hin, dass auf den Trockenstandorten der Tieflagen die einheimischen Baumarten an ihre physiologischen Grenzen stossen und längerfristig über alternative Baumarten nach-gedacht werden sollte. In den mittleren Lagen dürften Tro-ckenheit und Schadinsekten wie die Borkenkäfer die zukünf-tige Waldentwicklung steuern. In den Hochlagen hingegen werden sich die Wälder ausdehnen und besser wachsen als heute. Alle untersuchten Ökosystemleistungen werden ge-bietsweise starken Veränderungen unterworfen sein. Die dis-kutierten Bewirtschaftungsvarianten scheinen dazu geeignet, die Wasserverfügbarkeit der Bestände, hauptsächlich in tief-eren Lagen, zu erhöhen und dadurch die Widerstandskraft der Bäume gegenüber Trockenperioden vorübergehend zu stärken. Es ist aber davon ausgehen, dass nur verhältnismäs-sig starke Eingriffe wesentliche Effekte erzielen können. Die Verknüpfung von Umweltmonitoring, Feldexperimenten und Modellierung unter Miteinbezug von Ökosystemleistungen ist vielversprechend, da sie eine differenzierte Abschätzung des zukünftigen Landschaftswandels und seiner Effekte auf die Waldleistungen ermöglicht. Y1 - 2012 U6 - http://dx.doi.org/10.3188/szf.2012.0481 SN - 2235-1469 (Online) SN - 0036-7818 (Print) VL - 163 IS - 12 SP - 481 EP - 492 PB - Schweizerischer Forstverein CY - Zürich ER - TY - JOUR A1 - Weber, Pascale A1 - Rigling, Andreas A1 - Eilmann, Britta A1 - Mayer, Phillip A1 - Wohlgemuth, Thomas A1 - Dobbertin, Matthias T1 - Verjüngung und Konkurrenz der Flaumeiche im Wallis JF - Informationsblatt Wald Y1 - 2008 SN - 1661-5859 (Online) SN - 1424-5701 (Print) SN - 1661-5832 (Print) IS - 22 SP - 1 EP - 3 ER - TY - JOUR A1 - Eilmann, Britta A1 - Zweifel, Roman A1 - Buchmann, Nina A1 - Fonti, Patrick A1 - Rigling, Andreas T1 - Drought-induced adaptation of the xylem in Scots pine and pubescent oak JF - Tree Physiology Y1 - 2009 U6 - http://dx.doi.org/10.1093/treephys/tpp035 SN - 0829-318X (Print) SN - 1758-4469 (Online) VL - 29 IS - 8 SP - 1011 EP - 1020 PB - Heron CY - Victoria, BC ER - TY - JOUR A1 - Lévesque, Mathieu A1 - Siegwolf, Rolf A1 - Eilmann, Britta A1 - Saurer, Matthias A1 - Rigling, Andreas T1 - Increased water-use efficiency does not lead to enhanced tree growth under xeric and mesic conditions JF - New Phytologist Y1 - 2014 U6 - http://dx.doi.org/10.1111/nph.12772 SN - 1469-8137 (Online) SN - 0028-646X (Print) VL - 203 IS - 1 SP - 94 EP - 109 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Dobbertin, Matthias A1 - Rigling, Andreas T1 - Growth response of Scots pine with different crown transparency status to drought release JF - Annals of Forest Science Y1 - 2013 U6 - http://dx.doi.org/10.1007/s13595-013-0310-z SN - 1286-4560 (Print) SN - 1297-966X (Online) VL - 70 IS - 7 SP - 685 EP - 693 PB - Springer CY - Cham ER - TY - JOUR A1 - Lévesque, Mathieu A1 - Saurer, Matthias A1 - Siegwolf, Rolf A1 - Eilmann, Britta A1 - Brang, Peter A1 - Bugmann, Harald A1 - Rigling, Andreas T1 - Drought response of five conifer species under contrasting water availability suggests high vulnerability of Norway spruce and European larch JF - Global Change Biology Y1 - 2013 U6 - http://dx.doi.org/10.1111/gcb.12268 SN - 1365-2486 (Online) SN - 1354-1013 (Print) VL - 19 IS - 10 SP - 3184 EP - 3199 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Rigling, Andreas A1 - Bigler, Christof A1 - Eilmann, Britta A1 - Feldmeyer-Christe, Elisabeth A1 - Gimmi, Urs A1 - Ginzler, Christian A1 - Graf, Ulrich A1 - Mayer, Phillip A1 - Vacchiano, Giorgio A1 - Weber, Pascal A1 - Wohlgemuth, Thomas A1 - zweifel, Roman A1 - Dobbertin, Matthias T1 - Driving factors of a vegetation shift from Scots pine to pubescent oak in dry Alpine forests JF - Global Change Biology N2 - An increasing number of studies have reported on forest declines and vegetation shifts triggered by drought. In the Swiss Rhone valley (Valais), one of the driest inner-Alpine regions, the species composition in low elevation forests is changing: The sub-boreal Scots pine (Pinus sylvestris L.) dominating the dry forests is showing high mortality rates. Concurrently the sub-Mediterranean pubescent oak (Quercus pubescens Willd.) has locally increased in abundance. However, it remains unclear whether this local change in species composition is part of a larger-scale vegetation shift. To study variability in mortality and regeneration in these dry forests we analysed data from the Swiss national forest inventory (NFI) on a regular grid between 1983 and 2003, and combined it with annual mortality data from a monitoring site. Pine mortality was found to be highest at low elevation (below 1000 m a.s.l.). Annual variation in pine mortality was correlated with a drought index computed for the summer months prior to observed tree death. A generalized linear mixed-effects model indicated for the NFI data increased pine mortality on dryer sites with high stand competition, particularly for small-diameter trees. Pine regeneration was low in comparison to its occurrence in the overstorey, whereas oak regeneration was comparably abundant. Although both species regenerated well at dry sites, pine regeneration was favoured at cooler sites at higher altitude and oak regeneration was more frequent at warmer sites, indicating a higher adaptation potential of oaks under future warming. Our results thus suggest that an extended shift in species composition is actually occurring in the pine forests in the Valais. The main driving factors are found to be climatic variability, particularly drought, and variability in stand structure and topography. Thus, pine forests at low elevations are developing into oak forests with unknown consequences for these ecosystems and their goods and services. Y1 - 2012 U6 - http://dx.doi.org/10.1111/gcb.12038 SN - 1354-1013 (Print) SN - 1365-2486 (Online) VL - 19 IS - 1 SP - 229 EP - 240 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Stojnic, Srdjan A1 - Sass-Klaassen, Ute G. M. A1 - Orlovic, Sasa A1 - Matovic, Bratislav A1 - Eilmann, Britta T1 - Plastic growth response of European beech provenances to dry site conditions T2 - IAWA Journal / International Association of Wood Anatomists Y1 - 2013 U6 - http://dx.doi.org/10.1163/22941932-00000038 SN - 0928-1541 (Print) SN - 2294-1932 (Online) VL - 34 IS - 4 SP - 475 EP - 484 PB - Brill CY - Leiden ER - TY - JOUR A1 - Feichtinger, Linda M. A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Rigling, Andreas T1 - Trait-specific responses of Scots pine to irrigation on a short vs long time scale JF - Tree Physiology Y1 - 2015 U6 - http://dx.doi.org/10.1093/treephys/tpu114 SN - 1758-4469 (Online) SN - 0829-318X (Print) N1 - Ab 12 Monaten nach Veröffentlichung kostenfrei zugänglich. VL - 35 IS - 00 SP - 1 EP - 12 PB - Heron CY - Victoria, BC ER - TY - BOOK A1 - Hallmann, Willi T1 - (Meine) Erinnerungen an Jesco von Puttkamer : zusammengestellt anlässlich des Todes von Jesco von Puttkamer am 27. Dezember 2012 Y1 - 2015 SN - 978-3-86460-271-9 ; 3-86460-271-8 PB - Pro BUSINESS digital printing Deutschlang GmbH CY - Berlin ER - TY - JOUR A1 - Fonti, Patrick A1 - von Arx, Georg A1 - García-González, Ignacio A1 - Eilmann, Britta A1 - Sass-Klaassen, Ute G. W. A1 - Gärtner, Holger A1 - Eckstein, Dieter T1 - Studying global change through investigation of the plastic responses of xylem anatomy in tree rings JF - New Phytologist N2 - Variability in xylem anatomy is of interest to plant scientists because of the role water transport plays in plant performance and survival. Insights into plant adjustments to changing environmental conditions have mainly been obtained through structural and functional comparative studies between taxa or within taxa on contrasting sites or along environmental gradients. Yet, a gap exists regarding the study of hydraulic adjustments in response to environmental changes over the lifetimes of plants. In trees, dated tree-ring series are often exploited to reconstruct dynamics in ecological conditions, and recent work in which wood-anatomical variables have been used in dendrochronology has produced promising results. Environmental signals identified in water-conducting cells carry novel information reflecting changes in regional conditions and are mostly related to short, sub-annual intervals. Although the idea of investigating environmental signals through wood anatomical time series goes back to the 1960s, it is only recently that low-cost computerized image-analysis systems have enabled increased scientific output in this field. We believe that the study of tree-ring anatomy is emerging as a promising approach in tree biology and climate change research, particularly if complemented by physiological and ecological studies. This contribution presents the rationale, the potential, and the methodological challenges of this innovative approach. Y1 - 2010 U6 - http://dx.doi.org/10.1111/j.1469-8137.2009.03030.x SN - 1469-8137 (Online) SN - 0028-646X (Print) VL - 185 IS - 1 SP - 42 EP - 53 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Dobbertin, Matthias A1 - Eilmann, Britta A1 - Bleuler, Peter A1 - Giuggiola, Arnaud A1 - Graf Pannatier, Elisabeth A1 - Landolt, Werner A1 - Schleppi, Patrick A1 - Rigling, Andreas T1 - Effect of irrigation on needle morphology, shoot and stem growth in a drought-exposed Pinus sylvestris forest JF - Tree Physiology N2 - In Valais, Switzerland, Scots pines (Pinus sylvestris L.) are declining, mainly following drought. To assess the impact of drought on tree growth and survival, an irrigation experiment was initiated in 2003 in a mature pine forest, approximately doubling the annual precipitation. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Seven irrigated and six control trees were felled in 2006, and needles, stem discs and branches were taken for growth analysis. Irrigation in 2004 and 2005, both with below-average precipitation, increased needle size, area and mass, stem growth and, with a 1-year delay, shoot length. This led to a relative decrease in tree crown transparency (−14%) and to an increase in stand LAI (+20%). Irrigation increased needle length by 70%, shoot length by 100% and ring width by 120%, regardless of crown transparency. Crown transparency correlated positively with mean needle size, shoot length and ring width and negatively with specific leaf area. Trees with high crown transparency (low growth, short needles) experienced similar increases in needle mass and growth with irrigation than trees with low transparency (high growth, long needles), indicating that seemingly declining trees were able to ‘recover’ when water supply became sufficient. A simple drought index before and during the irrigation explained most of the variation found in the parameters for both irrigated and control trees. Y1 - 2010 U6 - http://dx.doi.org/10.1093/treephys/tpp123 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 30 IS - 3 SP - 346 EP - 360 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Siegwolf, Rolf A1 - Saurer, Matthias A1 - Cherubini, Paolo A1 - Rigling, Andreas T1 - Fast response of Scots pine to improved water availability reflected in tree-ring width and δ13C JF - Plant, Cell and Environment N2 - Drought-induced forest decline, like the Scots pine mortality in inner-Alpine valleys, will gain in importance as the frequency and severity of drought events are expected to increase. To understand how chronic drought affects tree growth and tree-ring δ13C values, we studied mature Scots pine in an irrigation experiment in an inner-Alpine valley. Tree growth and isotope analyses were carried out at the annual and seasonal scale. At the seasonal scale, maximum δ13C values were measured after the hottest and driest period of the year, and were associated with decreasing growth rates. Inter-annual δ13C values in early- and latewood showed a strong correlation with annual climatic conditions and an immediate decrease as a response to irrigation. This indicates a tight coupling between wood formation and the freshly produced assimilates for trees exposed to chronic drought. This rapid appearance of the isotopic signal is a strong indication for an immediate and direct transfer of newly synthesized assimilates for biomass production. The fast appearance and the distinct isotopic signal suggest a low availability of old stored carbohydrates. If this was a sign for C-storage depletion, an increasing mortality could be expected when stressors increase the need for carbohydrate for defence, repair or regeneration. Y1 - 2010 U6 - http://dx.doi.org/10.1111/j.1365-3040.2010.02153.x SN - 1365-3040 (Online) SN - 0140-7791 (Print) VL - 33 IS - 8 SP - 1351 EP - 1360 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Egli, Simon A1 - Ayer, François A1 - Peter, Martina A1 - Eilmann, Britta A1 - Rigling, Andreas T1 - Is forest mushroom productivity driven by tree growth? Results from a thinning experiment JF - Annals of Forest Science N2 - • Most of the edible forest mushrooms are mycorrhizal and depend on carbohydrates produced by the associated trees. Fruiting patterns of these fungi are not yet fully understood since climatic factors alone do not completely explain mushroom occurrence. • The objective of this study was to retrospectively find out if changing tree growth following an increment thinning has influenced the diversity patterns and productivity of associated forest mushrooms in the fungus reserve La Chanéaz, Switzerland. • The results reveal a clear temporal relationship between the thinning, the growth reaction of trees and the reaction of the fungal community, especially for the ectomycorrhizal species. The tree-ring width of the formerly suppressed beech trees and the fruit body number increased after thinning, leading to a significantly positive correlation between fruit body numbers and tree-ring width. • Fruit body production was influenced by previous annual tree growth, the best accordance was found between fruit body production and the tree-ring width two years previously. • The results support the hypothesis that ectomycorrhizal fruit body production must be linked with the growth of the associated host trees. Moreover, the findings indicate the importance of including mycorrhizal fungi as important players when discussing a tree as a carbon source or sink. Y1 - 2010 U6 - http://dx.doi.org/10.1051/forest/2010011 SN - 1286-4560 (Print) SN - 1297-966X (Online) VL - 67 IS - 5 SP - 509 PB - Springer CY - Paris ER - TY - JOUR A1 - Rigling, Andreas A1 - Eilmann, Britta A1 - Koechli, Roger A1 - Dobbertin, Matthias T1 - Mistletoe-induced crown degradation in Scots pine in a xeric environment N2 - Increasing Scots pine (Pinus sylvestris L.) mortality has been recently observed in the dry inner valleys of the European Alps. Besides drought, infection with pine mistletoe (Viscum album ssp. austriacum) seems to play an important role in the mortality dynamics of Scots pines, but how mistletoes promote pine decline remains unclear. To verify whether pine mistletoe infection weakens the host via crown degradation, as observed for dwarf mistletoes, we studied the negative effects of pine mistletoe infestation on the photosynthetic tissues and branch growth of pairs of infested and non-infested branches. Pine mistletoe infection leads to crown degradation in its host by reducing the length, the radial increment, the ramification, the needle length and the number of needle years of the infested branches. This massive loss in photosynthetic tissue results in a reduction in primary production and a subsequent decrease in carbohydrate availability. The significant reduction in needle length due to mistletoe infection is an indication for a lower water and nutrient availability in infested branches. Thus, mistletoe infection might lead to a decrease in the availability of water and carbohydrates, the two most important growth factors, which are already shortened due to the chronic drought situation in the area. Therefore, pine mistletoe increases the risk of drought-induced mortality of its host when growing in a xeric environment. Y1 - 2010 U6 - http://dx.doi.org/10.1093/treephys/tpq038 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 30 IS - 7 SP - 845 EP - 832 PB - Oxford University Press CY - Oxford ER -