Landscape-scale spatial patterns of winter injury to red spruce foliage in a year of heavy region-wide injury

Abstract

Red spruce (Picea rubens Sarg.) winter injury is caused by freezing damage that results in the abscission of the most recent foliar age-class. Injury was widespread and severe in the northeastern United States in 2003 and was assessed at multiple elevations at 23 sites in Vermont and adjacent states. This paper presents a spatial analysis of these injury assessments. Relationships between winter injury on dominant and codominant spruce trees and elevation, latitude, longitude, slope, and aspect were investigated with least squares regression and geographically weighted regression. Results of these analyses indicate that injury increased (1) with elevation; (2) from east to west; (3) with the degree to which plots faced west, except at the highest elevations, where injury was uniformly severe; (4) with increases in slope steepness at higher elevations, or with decreases in slope steepness at lower elevations; and (5) with the degree to which plots faced south, except at the highest elevations in northern locations, where injury was uniformly severe. Because injury was greater in areas that have historically received higher levels of acid and nitrogen deposition -western portions of the study region, west-facing slopes, and higher elevations -observed patterns of injury support the hypothesis that acidic and (or) nitrogen deposition act on a landscape scale to exacerbate winter injury. Greater injury on south-facing slopes suggests that sun exposure exacerbates injury or its expression. Résumé :Les dommages causés par le froid chez l'épinette rouge (Picea rubens Sarg.) sont dus au gel qui entraîne l'abscission de la classe de feuillage la plus récente. Les dommages étaient largement répandus et sévères dans le nordest des États-Unis en 2003 et ont été évalués à plusieurs altitudes dans 23 sites situés au Vermont et dans les États adjacents. Cet article présente une analyse spatiale de l'évaluation de ces dommages. Les relations entre les dommages causés par le froid sur les tiges d'épinette dominantes et codominantes et l'altitude, la latitude, la longitude, la pente et l'exposition ont été étudiées avec la méthode des moindres carrés et la régression géographiquement pondérée. Les ré-sultats de ces analyses indiquent que les dommages augmentent : (1) avec l'altitude; (2) d'est en ouest; (3) plus les parcelles sont exposées à l'ouest, excepté aux plus hautes altitudes où la sévérité des dommages est uniforme; (4) avec l'augmentation de la pente à haute altitude ou avec la diminution de la pente à basse altitude; et (5) plus les parcelles sont exposées au sud, excepté aux plus hautes altitudes dans les endroits situés au nord où la sévérité des dommages était plus uniforme. Parce que les dommages étaient plus importants dans les zones qui ont historiquement reçu des quantités plus élevées de dépôts acides et d'azote, soit la partie ouest de la région étudiée, les pentes exposées à l'ouest et les secteurs situés en altitude, les patrons de dommages que les auteurs ont observés supportent l'hypothèse que les dépôts ac...

Regional patterns in foliar 15N across a gradient of nitrogen deposition in the northeastern US

“…Lazarus et al (2006) reported that conifers in the western part of our study region were more stressed than trees in the eastern part of the region. For red spruce, that stress is associated with reduced freezing tolerance and increased winter injury.…”

“…These include soil and surface water acidification, plant nutrient imbalances which may ultimately result in declines in forest health and, over the long term, changes in species composition (Nihlgard, 1985;Aber et al, 1989;Schaberg et al, 2002). Trees at higher elevations are typically affected more than those at lower elevations, because of elevated N deposition and poor site quality (Johnson et al, 1992;Lazarus et al, 2006). Different tree species may exhibit varying levels of susceptibility to elevated N inputs; often coniferous species, which have lower biological N demand and are better adapted to poorer quality/ low nutrient sites are impacted more by increases in N availability (Southern Forest Resource Assessment;SOFRA, 2002).…”

A rapid upward shift of a forest ecotone during 40 years of warming in the Green Mountains of Vermont

“…3), which was likely able to capture canopy space opened by mortality of red spruce and paper birch. The decline of the red spruce is likely related to increased winter injury from acidic deposition, which is more severe at higher elevations (33,34). Paper birch may also be adversely affected by increasing frequency of freeze-thaw events associated with climate change (35).…”

A case of extensive conifer needle browning in northwestern Ontario in 2012: Winter drying or freezing damage?

“…in the northeastern United States, both winter desiccation (Curry and Church 1952, Hadley et al 1991 and dehardening/freezing damage (Peart et al 1991;Perkins and Adams 1995;Strimbeck et al 1995;Lazarus et al 2004Lazarus et al , 2006 have been suggested as causal factors. In this paper we examine the possible causes of widespread conifer damage in northern Ontario and identify next steps to improve our understanding of this recurring phenomenon.…”

“…Some researchers believe that the damage is associated with fluctuations of warm and freezing temperatures in winter months (Henson 1952, Cayford et al 1959, Robin and Susut 1974. In the well-studied syndrome of red spruce winter injury in the northeastern United States, both winter desiccation (Curry and Church 1952, Hadley et al 1991 and dehardening/freezing damage (Peart et al 1991;Perkins and Adams 1995;Strimbeck et al 1995;Lazarus et al 2004Lazarus et al , 2006 have been suggested as causal factors. In this paper we examine the possible causes of widespread conifer damage in northern Ontario and identify next steps to improve our understanding of this recurring phenomenon.…”