Treesearch

Phenotypic trait variation can be linked to genomic sequence variation. These differences range from a single nucleotide to larger insertion and deletion (indel) of chromosomal segments. Indels can change the copy number of affected genes, which can create complex phenotypic trait variation through effects on gene expression. For example, gene dosage variation has been associated with various human chronic diseases. Here we systematically explored the effect of induced gene dosage variation on quantitative trait variation in Populus. We show that gene dosage variation at specific chromosoma...

Adventitious roots occur naturally in many species and can also be induced from explants of some tree species including Populus, providing an important means of clonal propagation. Auxin has been identified as playing a crucial role in adventitious root formation, but the associated molecular regulatory mechanisms need to be elucidated. In this study, we examined the role of PagFBL1, the hybrid poplar (Populus alba× P. glandulosa clone 84K) homolog of Arabidopsis auxin receptor TIR1, in adventitious root formation in poplar. Similar to the distribution pattern of auxin during initiation of...

Secondary growth from a vascular cambium, present today only in seed plants and isoetalean lycophytes, has a 400‐million‐yr evolutionary history that involves considerably broader taxonomic diversity, most of it hidden in the fossil record. Approaching vascular cambial growth as a complex developmental process, we review data from living plants and fossils that reveal diverse modes of secondary growth. These are consistent with a modular nature of secondary growth, when considered as a tracheophyte‐wide structural feature. This modular perspective identifies putative constituent development...

Societal Impact Statement Drought plays a conspicuous role in forest mortality, and is expected to become more severe in future climate scenarios. Recent surges in drought‐associated forest tree mortality have been documented worldwide. For example, recent droughts in California and Texas killed approximately 129 million and 300 million trees, respectively. Drought has also induced acute pine tree mortality across east‐central China, and across extensive areas in southwest China. Understanding the biological processes that enable trees to modify wood development to mitigate the adverse...

Thousand cankers disease is caused by the coalescence of numerous Geosmithia morbida cankers on branches and stems of Juglans species, leading to branch dieback and eventual tree death. The fungus sporulates in galleries of the walnut twig beetle (Pityophthorus juglandis), allowing for acquisition of pathogen propagules and its subsequent transmission to other branches or trees following adult emergence. Recently, G. morbida has been isolated from Xylosandrus crassiusculus and Xyleborinus saxesenii collected in Ohio and Stenomimus pallidus collected in Indiana. These beetles are known to...

Barred owls (Strix varia) are forest‐dwelling owls, native to eastern North America, with populations that expanded westward into the range of the spotted owl (Strix occidentalis). Barred owls exert an overwhelmingly negative influence on spotted owls, thereby threatening spotted owl population viability where the species co‐occur. In this review, we provide an overview of the barred owl’s range expansion and detail and synthesize previously published literature on spotted and barred owls within the range of the spotted owl as related to potential future outcomes for the northern spotted...

There is no one-size-fits-all way to successfully implement forest landscape restoration (FLR). Complex socio-ecological systems present challenges and opportunities that can best be met with a systematic framework for designing, planning, steering, and monitoring FLR projects to meet diverse needs. Project cycle management is an iterative, adaptive, hierarchical framework with recurring consultations among stakeholders that can enhance the likelihood of FLR success.

Reliable estimates of tree growth and wood yield are fundamental to support the management of restored forests and better reconcile the objectives of recovering biodiversity with the provision of ecosystem services. In this study, wood standing volumes and tree biomass stocks were estimated in di erent ecological restoration systems and at two sites with contrasting soil fertility, in order to evaluate the potential trade-o s between biodiversity and forest production. At each site, a complete randomized block design, with three replications of six treatments, was established in 1997–1998:...

An economic model of the global forest sector was used to estimate the carbon mitigating potential of the world’s forests to 2065 for 180 countries assuming future socioeconomic trends that do not change markedly from historical patterns, consistent with the IPCC-SSP2. Forest carbon pools were broken down into four categories; (i) above-ground and below-ground biomass, (ii) forest soil, (iii) dead wood and litter, and (iv) harvested wood products. Changes in forest carbon storage were driven by the dynamic relationship between endogenously determined timber harvest, wood product consumption...

The hemlock woolly adelgid (HWA), Adelges tsugae (Annand), has become one of the most important and impactful non-native forest insect pests in eastern North America (Foster et al. 2014). Over the past 30 years, the decline of hemlock trees has generated a passionate and energized response by landowners, public and private land managers, and the general public, leading to federal, state, and grass-roots efforts and support to help fight this invader. The management effort for HWA has been covered repeatedly in the popular media, especially when the pest and its impact have spread into new...