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Modeling environmental spatial heterogeneity can improve the efficiency of forest tree genomic evaluation. Furthermore, genotyping costs can be lowered by reducing the number of markers needed. We investigated the impact on variance components, breeding value accuracy, and bias of two phenotypic data adjustments (experimental design and autoregressive spatial models), and a relationship matrix calculated from a subset of markers selected for their ability to infer ancestry. Using a multiple-trait multiple-site single-step Genomic Best Linear Unbiased Prediction (ssGBLUP) approach, four scenarios (2 phenotype adjustments × 2 marker sets) were applied to diameter at breast height (DBH), height (HT), and resistance to western gall rust (WGR) in four open-pollinated progeny trials of lodgepole pine, with 1490 (out of 11,188) trees genotyped with 25,099 SNPs. As a control, we fitted the conventional ABLUP model using pedigree information. The highest heritability estimates were achieved for the ABLUP followed closely by the ssGBLUP with the full marker set and using the spatial phenotype adjustments. The highest predictive ability was obtained by using a reduced marker subset (8000 SNPs) when either the spatial (DBH: 0.429, and WGR: 0.513) or design (HT: 0.467) phenotype corrections were used. No significant difference was detected in prediction bias among the six fitted models, and all values were close to 1 (0.918–1.014). Results demonstrated that selecting informative markers, such as those capturing ancestry, can improve the predictive ability. The use of spatial correlation structure increased traits’ heritability and reduced prediction bias, while increases in predictive ability were trait-dependent.

ABSTRACTLeaf photosynthetic characteristics could be determinant factors to identify the most productive clones of hybrid poplars (Populusspp.) and willows (Salixspp.). Photosynthetic acclimation of hybrid poplars and willows was studied under greenhouse conditions. Seven Populusand five Salixclones were grown for 3 months at three spacings [20 × 20, 35 × 35, and 60 × 60 cm] and two nitrogen (N) levels (20 and 200 μg g−1). There were no significant spacing effects on leafless aboveground biomass per tree (AGBT) and height. Clonal acclimation to higher density was associated to increases in leaf area index (LAI) by 347% and specific leaf area (SLA) by 13% despite decreased leaf N content per unit leaf area (Narea) by 31%. There were no changes in net CO2assimilation rate (A) and photosynthetic N-use efficiency in the ambient light condition (PNUEamb) within different spacings. The N addition alleviated competition effects by maximizing leaf area (LA) and SLA. Compared with less productive clones, more productive clones had 28% greater SLA, greater LA and AGBT per unit of increase in Nareaover all treatments. The increased development of LA and SLA under high planting density is a key indicator of more productive clones.

This paper describes the differences between expert and public perceptions of plantation forestry and calls for greater public participation in the development and establishment of plantations. The debate over the social acceptability of varying land-uses is essentially a debate over how land is valued and the effects of land-use change on local peoples. This study reports the findings from 31 interviews with key informants, indicating central themes such as farming identity, trust and economic competition as important to an overall assessment of community perceptions of hybrid poplar plantations. Specifically, we suggest that all of these themes are linked to complex attachments to traditional rural land-use and fear of externally motivated change. Findings from this study contribute to a greater understanding of the public values at stake around tree plantations, where experts have emphasised ecological impacts and economic trade-offs and generally disregarded the social concerns raised above.

Several letters to the editor are presented in response to various articles published in this journal including "West Virginia's Hammons Family," by Wayne Howard in the Winter 2014 issue, "George Karos: Martinburg's Pharmacist Mayor," by John Lilly in the Winter 2014 issue and "Wood Gathering Day," by Jack Furbee in the Winter 2014 issue.