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Ecological studies in diverse environmental fields require accurate climate data for point locations that are often distant from reliable public weather stations. 'Onsite' micro weather stations can be established directly at research locations, but purchase, establishment, and maintenance costs and data gaps can limit their feasibility. Alternatively, climate data for point locations can be predicted from ClimateNA, a publicly available software package, but the prediction accuracy in remote and mountainous locations is uncertain. We compared ClimateNA predictions with observations from onsite weather stations located at 11 interior spruce provenance trials in British Columbia, Canada. We found that ClimateNA predictions were highly accurate for temperature variables but moderate for precipitation variables when compared with onsite weather data. Growth response functions developed with the two data sources showed similar shapes for temperature variables. Our results suggest that (1) temperature variables can be accurately predicted at remote and mountainous locations using ClimateNA; (2) precipitation variables are more accurately predicted with ClimateNA than with onsite weather stations, which are considerably affected by random factors; and (3) response functions provide an effective, independent tool to assess alternative sources of climate data. Our results recommend the use of ClimateNA over onsite weather stations, except where highly accurate precipitation data are required, in which case, high-quality onsite weather stations must be established and carefully maintained. Key words: onsite weather station, response function, genecology, ClimateNA, model prediction accuracy Les etudes ecologiques dans divers domaines de l'environnement necessitent des donnees climatiques precises pour des emplacements ponctuels qui sont souvent eloignes de stations meteorologiques publiques fiables. Des microstations meteorologiques << sur place >> peuvent etre installees directement sur les sites de recherche, mais les couts d'achat, d'installation et d'entretien ainsi que les lacunes en matiere de donnees peuvent en limiter la faisabilite. Il est egalement possible de predire les donnees climatiques pour des points precis a l'aide de ClimateNA, un logiciel accessible au public, mais la precision des predictions dans les regions eloignees et montagneuses est incertaine. Nous avons compare les predictions de ClimateNA avec les observations des stations meteorologiques sur place situees dans 11 essais de provenance de l'epicea interieur en Colombie-Britannique, au Canada. Nous avons constate que les predictions de ClimateNA etaient tres precises pour les variables de temperature, mais moderees pour les variables de precipitation lorsqu'elles etaient comparees aux donnees meteorologiques sur place. Les fonctions de reponse de croissance developpees avec les deux sources de donnees ont montre des formes similaires pour les variables de temperature. Nos resultats suggerent que : (1) les variables de temperature peuvent etre predites avec precision dans des endroits eloignes et montagneux a l'aide de ClimateNA; (2) les variables de precipitations sont predites avec plus de precision avec ClimateNA qu'avec les stations meteorologiques sur place, qui etaient considerablement affectees par des facteurs aleatoires; et (3) les fonctions de reponse fournissent un outil efficace et independant pour evaluer les sources alternatives de donnees climatiques. Nos resultats recommandent l'utilisation de ClimateNA plutot que des stations meteorologiques sur place, sauf lorsque des donnees de precipitations tres precises sont requises, auquel cas des stations meteorologiques de haute qualite sur place doivent etre etablies et soigneusement entretenues. [Traduit par la Redaction] Mots-cles: station meteorologique sur place, fonction de reponse, genecologie, ClimateNA, precision de la prediction du modele, 1. Introduction With the growing importance of climate-change-related studies in ecological and biological sciences, the demand for accurate climate data increases (Haylock et al. 2008; World Bank 2012; Rehfeldt et [...]

Climate change is expected to outpace the rate at which populations of forest trees can migrate. Hence, in forestry there is growing interest in intervention strategies such as assisted migration to mitigate climate change impacts. However, until now the primary focus when evaluating candidates for assisted migration has been mean or maximum performance. We explore phenotypic plasticity as a potentially new avenue to help maintain the viability of species and populations in the face of climate change. Capitalizing on large, multi-site international provenance trials of four economically and ecologically important forest tree species (Fagus sylvatica, Picea abies, Picea engelmannii, Pinus contorta), we quantify growth stability as the width of the response function relating provenance growth performance and trial site climate. We found significant differences in growth stability among species, with P. engelmannii being considerably more stable than the other three species. Additionally, we found no relationship between growth performance and growth stability of provenances, indicating that there are fast-growing provenances with a broad climate optimum. In two of the four species, provenances' growth stability showed a significant relationship with the climate of the seed source, the direction of which depends on the species. When taken together with data on growth performance in different climate conditions, a measure of growth stability can improve the choice of species and provenances to minimize future risks in forest restoration and reforestation. [ABSTRACT FROM AUTHOR]

Common‐garden trials of forest trees provide phenotype data used to assess growth and local adaptation; this information is foundational to tree breeding programs, genecology, and gene conservation. As jurisdictions consider assisted migration strategies to match populations to suitable climates, in situ progeny and provenance trials provide experimental evidence of adaptive responses to climate change. We used drone technology, multispectral imaging, and digital aerial photogrammetry to quantify spectral traits related to stress, photosynthesis, and carotenoids, and structural traits describing crown height, size, and complexity at six climatically disparate common‐garden trials of interior spruce (Picea engelmannii × glauca) in western Canada. Through principal component analysis, we identified key components of climate related to temperature, moisture, and elevational gradients. Phenotypic clines in remotely sensed traits were analyzed as trait correlations with provenance climate transfer distances along principal components (PCs). We used traits showing clinal variation to model best linear unbiased predictions for tree height (R2 =.98–.99, root mean square error [RMSE] = 0.06–0.10 m) and diameter at breast height (DBH, R2 =.71–.97, RMSE = 2.57–3.80 mm) and generated multivariate climate transfer functions with the model predictions. Significant (p <.05) clines were present for spectral traits at all sites along all PCs. Spectral traits showed stronger clinal variation than structural traits along temperature and elevational gradients and along moisture gradients at wet, coastal sites, but not at dry, interior sites. Spectral traits may capture patterns of local adaptation to temperature and montane growing seasons which are distinct from moisture‐limited patterns in stem growth. This work demonstrates that multispectral indices improve the assessment of local adaptation and that spectral and structural traits from drone remote sensing produce reliable proxies for ground‐measured height and DBH. This phenotyping framework contributes to the analysis of common‐garden trials towards a mechanistic understanding of local adaptation to climate. [ABSTRACT FROM AUTHOR]

Considers race differences in the determinants of social support network characteristics using data from Established Populations for Epidemiological Studies of the Elderly. Focuses on the extent to which race differences in network dimensions are present and whether variations can be attributed to social structural positions held. Results indicate that several race differences persist even when controlling for social structural variables. (JDM)

In forestry, science-based seed transfer systems, the foundation of effective reforestation programs, will likely be used in some form to mitigate the negative effects of climate change. In this study, we developed fixed and focal point seed transfer systems for interior spruce (Picea glauca (Moench) Voss, Picea engelmannii Parry ex Engelm., and their hybrids) in British Columbia, Canada, and compared the effectiveness of both systems. Growth, phenology, and physiology traits were measured for 112 populations, and population means were transformed to principal components that were modeled using climate variables and multiple regression analysis. Compared with the fixed seed zone system, the focal point system had a greater area of seed use for a given risk of maladaptation. The relationship between growth and adaptive distance (i. e., adaptive similarity between test populations and populations local to test sites) was used to calculate critical seed transfer distances for focal point seed zones, which were defined according to expected forfeiture of growth. Changes in climate observed over the past 100 years and predicted in the next one third of a rotation were used to calculate appropriate assisted migration distances and develop methods for incorporating assisted migration into a focal point seed transfer system. Resume: etant le fondement de programmes efficaces de reboisement en foresterie, les systemes de transfert de semences qui reposent sur des donnees scientifiques seront probablement utilises sous une forme ou une autre afin d'attenuer les effets negatifs des changements climatiques. La presente etude avait pour but de developper des systemes de transfert des semences bases sur les points fixes et focaux pour l'epinette de l'interieur (Picea glauca (Moench) Voss, Picea engelmannii Parry ex Engelm. et leurs hybrides) en Colombie-Britannique, au Canada, et de comparer l'efficacite des deux types de systeme. Des caracteres relies a la croissance, la phenologie et la physiologie ont ete mesures chez 112 populations et les moyennes de populations ont ete transformees en composantes principales qui ont ete modelisees a l'aide des variables climatiques et de l'analyse de regression multiple. Comparativement au systeme de zones semencieres base sur les points fixes, le systeme a points focaux produisait de plus grandes zones d'utilisation des semences pour un risque donne de mesadaptation. La relation entre la croissance et la distance reliee a l'adaptation (c.-a-d. la similitude d'adaptation entre les populations d'elevage et les populations locales en reference aux sites experimentaux) a ete utilisee pour estimer les distances critiques de transfert des semences pour les zones semencieres basees sur les points focaux, telles que definies selon la baisse anticipee de croissance. Les changements climatiques observes durant les 100 dernieres annees et predits pendant le premier tiers de la revolution ont ete utilises pour estimer les distances appropriees de migration assistee et pour developper des methodes qui incorporent la selection assistee au systeme de transfert des semences base sur les points focaux., Introduction Climate change is expected to result in forests becoming increasingly maladapted in many regions as the climates they experience depart from the climates in which they evolved (Schmidtling 1994; [...]

As a hand-held, portable tool capable of assessing wood density of standing trees quickly and inexpensively, the Resistograph holds considerable potential application for evaluating forest genetics field tests. However, phenotypic correlations between Resistograph density index values and values from conventional wood density assessment techniques are weak. In an effort to investigate the extent to which environmental, operator, or instrument factors may affect density index values, we evaluated the sensitivity of Resistograph measurements to seven experimental factors. Drill bit flexion (a measure of operator steadiness), moisture content of wood, and air temperature significantly affected Resistograph density index values, while the influence of knots is minimized at a vertical distance of 3 cm. Battery type, sharpness of the drill bit (at least up to 350 uses), and battery charge (at least up to 310 uses with a 12 V motorcycle battery) had no significant effect on density index. By ensuring that the operator remains steady while drilling, sampling only live trees, only when air temperatures are above freezing, and by drilling at least 3 cm vertical distance from knots, measurement error should be minimized. Three measurements per tree are required to estimate density index to within 3 units 19 times out of 20. Resume: En tant qu'outil portatif capable de mesurer rapidement et de maniere peu couteuse la densite du bois des arbres sur pied, le resistographe offre un potentiel considerable pour l'evaluation des tests de genetique forestiere sur le terrain. Cependant, les correlations phenotypiques entre les valeurs de l'indice de densite du resistographe et les valeurs obtenues avec les methodes conventionnelles de mesure de la densite sont faibles. Afin de determiner dans quelle mesure les facteurs relies a l'environnement, a l'operateur ou a l'instrument peuvent influencer les valeurs de l'indice de densite, nous avons evalue la sensibilite des mesures du resistographe a sept facteurs experimentaux. La flexion de la meche (une mesure de la stabilite de l'operateur), la teneur en humidite du bois et la temperature de l'air ont influence les valeurs de l'indice de densite du resistographe de maniere significative, alors que l'influence des noeuds etait negligeable a une distance verticale de trois cm. Le type de batterie, l'affutage de la meche (utilisation jusqu'a 350 fois au moins) et la charge de la batterie (utilisation jusqu'a 310 fois au moins avec une batterie de 12 V pour motocyclette) n'ont pas eu d'effet significatif sur la valeur de l'indice de densite. En s'assurant que l'operateur demeure stable en percant, que seuls des arbres vivants sont echantillonnes, que la temperature de l'air est au-dessus du point de congelation et en percant a une distance verticale d'au moins 3 cm d'un noeud, les erreurs de mesure devraient etre minimisees. Trois mesures par arbre sont requises pour estimer l'indice de densite a 3 unites pres, 19 fois sur 20. [Traduit par la Redaction], Introduction Wood density is an important indicator of wood strength (Evans and Ilic 2001) and must be incorporated into tree improvement programs to maintain wood quality as rotations shorten and [...]

Growth response functions (GRFs) that relate the growth of a population to the climate of the sites in which it is tested are gaining attention for their ability to predict impacts of climate change on tree growth. However, nonclimatic site to site variation introduces error into GRFs. Using data from a large lodgepole pine (Pinus contorta Dougl. ex Loud.) provenance test in British Columbia and the Yukon, Canada, a technique is presented that accounts for the effect of nonclimatic variation in GRFs. The mean height of the 'local' provenances at each test site was used to predict 'site height' from site climate variables in multiple regression. Residuals from the site height equation provided an index of the nonclimatic effect for each site and were included as a covariate in quadratic GRFs that related provenance height at each test site to mean annual temperature at each test site. Inclusion of the nonclimatic index in the model resulted in a moderate or large displacement of GRFs for 25% of the provenances, while increasing mean [R.sup.2] values for 138 of 140 provenances and decreasing the root mean squared error for 113 of 140 provenances. These results suggest that inclusion of the nonclimatic index in GRF models could substantially affect height predictions for some provenances and reduce prediction error for most provenances. Les fonctions de reaction de la croissance (FRC) qui relient la croissance d'une population au climat des stations oh elles sont testees gagnent en popularity; a cause de leur capacity; a predire les impacts des changements climatiques sur la croissance des arbres. Cependant, les variations non climatiques entre les stations introduisent des erreurs dans les FRC. A partir des donnees d'un test de provenance de pin tordu latifolie (Pinus contorta Dougl. ex Loud.) de grande envergure en Colombie-Britannique et au Yukon, au Canada, nous presentons une technique qui tient compte de l'effet des variations non climatiques dans les FRC. La hauteur moyenne des provenances <> a chaque endroit oU le test a ete etabli a ete utilisee pour predire, a l'aide de la regression multiple, la <> a partir des variables climatiques de la station. Les residus de l'equation de la hauteur specifique a la station ont fourni un indice de l'effet non climatique dans chaque station et ont etes inclus comme covariable dans des FRC quadratiques qui reliaient la hauteur de la provenance dans chaque station a la temperature annuelle moyenne de la station. L'introduction de l'indice non climatique dans le modele a produit un dylplacement modere a grand des FRC chez 25 % des provenances, a augmente la valeur moyenne du [R.sup.2] de 138 des 140 provenances et a diminue l'erreur quadratique moyenne chez 113 des 140 provenances. Ces resultats indiquent que l'introduction de l'indice non climatique dans les modeles de FRC pourrait substantiellement affecter les predictions de hauteur pour quelques provenances et diminuer l'erreur de prediction pour la plupart des provenances. [Traduit par la Redaction], Introduction With climate change raising the spectre of significant changes to forest productivity due to altered adaptation, provenance tests have encountered a resurgence of interest, as modellers attempt to mitigate [...]

Although there has been considerable interest in the effects of social support networks on various health outcomes for older adults, there has been little research directed toward the predictors of networks. In this study, we examine race differences in the determinants of social support network characteristics (size, frequency of interaction with network members, proportion of kin, and amount of support received and given to network members) using data from an older community sample drawn from the North Carolina site of the Established Populations for Epidemiologic Studies of the Elderly (EPESE) focusing on adults sixty-five and older (n = 4124). This research focuses on the extent to which race differences in network dimensions are present and whether these variations can be attributed to varying social structural positions held by African Americans and Whites. The results indicate that several race differences persist even when controlling for social structural variables. The structural argument and future implications are discussed.

Tree seed zones that are too large can compromise forest plantation health and productivity due to maladaptation arising from some populations being transferred long distances, whereas tree seed zones that are too small can result in unwarranted seed collections or excessive numbers of breeding zones. There has been little discussion, however, regarding the development and use of transfer functions for quantifying critical (i.e., safe) seed transfer distance (CSTD) or how artificial selection might affect CSTD. Using data from a large, multi-site provenance test for Douglas-fir and Interior spruce containing both genetically selected and wildstand seed sources, we illustrate an approach to quantify CSTD using Euclidean climate transfer distance modeled with a half-normal transfer function. A wide range of CSTDs was calculated and most transfer functions showed that selected seed sources were considerably taller than wildstand seed sources when transferred short or medium climate distances. Contrarily, selected seed sources were shorter than wildstand seed sources when transferred long climate distances. CSTDs were shorter for Douglas-fir than for spruce, and shorter when calculated using height rather than survival as the transfer function response variable. These findings suggest that (1) unfavorable changes in adaptation due to artificial selection will be observable only when seed is transferred considerably beyond the CSTD; (2) differences in adaptation between selected and wildstand seed classes may not warrant separate seed transfer guidelines for these seed classes; (3) British Columbia's Douglas-fir and Interior spruce breeding programs are generating significant height gain; (4) methods presented here produce logical transfer functions that can be used to calculate reliable site-specific CSTDs; (5) use of conservative (short) CSTDs may be advisable when tests are young; and (6) provenance tests should be located in disparate climates. [ABSTRACT FROM AUTHOR]

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Investigates genetics of fall and spring cold hardiness in two western Oregon breeding populations of Douglas-fir. Evaluation of influence of summer drought on ranking of seedlings from 40 open-pollinated families; Analysis of cold injuries due to natural frost event and artificial freeze testing; Cold injuries suffered by coastal and cascade population in fall; Effect of cold hardiness based on single shoot tissue on other tissues.

A response from the authors of an article on the role of extreme climatic change in assisted migration in forestry (forestry AM), that was published in a previous issue, is presented.