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Premise: Intraspecific variation in drought resistance traits, such as drought escape, appear to be frequent within wild, ruderal forb species. Understanding how these traits are arrayed across the landscape, particularly in association with climate, is critical to developing forbs for wildland restoration programs. Use of forbs is requisite for maintaining biological diversity and ecological services. Methods: Using 6074 greenhouse‐grown Chaenactis douglasii seedlings from 95 wild, seed‐sourced populations across the western United States, we recorded bolting phenology and estimated genome size using flow cytometry. Mixed‐effects regression models were used to assess whether climate of seed origin was predictive for bolting phenology and genome size. Results: Variation in bolting, reflecting an annual vs. perennial lifespan in this species, was observed in 8.7% of the plants, with bolting plants disproportionately occurring in locations with warm, arid climates. Populations with increasing heat and aridity were positively correlated with observed bolting (r = 0.61, p < 0.0001). About one‐third (22%) of the total (61%) lifespan variation was attributed to seed source climate and annual heat moisture index, a measure of aridity. Genome size had no significant effect on bolting. Projected climate modeling for mid‐century (2041–2070) supports an increasing occurrence of annual lifespan. Conclusions: Our analyses support a drought escape, bet‐hedging strategy in C. douglasii. Populations exposed to greater aridity exhibited a higher proportion of individuals with an annual lifespan. Drought escape leading to an annual lifespan can affect how seeds are propagated and deployed for climate‐informed restoration. [ABSTRACT FROM AUTHOR]

An increasing number of threats, both natural (e.g. fires, drought) and anthropogenic (e.g. agriculture, infrastructure development), are likely to affect both availability and quality of plants that grouse rely on for cover and food. As such, there is an increasing need to monitor plants and their use by grouse over space and time to better predict how changes in habitat quality influence the behavior of grouse. We use the greater sage-grouse Centrocercus urophasianus to showcase how new technology can be used to advance our understanding of the ecology, behavior and conservation of grouse. We demonstrate how laser, spectral and chemical detectors and unmanned aerial systems can be used to measure structural and phytochemical predictors of habitat quality at several spatial scales. We also demonstrate how advanced biotelemetry systems and robotic animals can be used to measure how habitat quality influences fine-scale habitat use, movement and reproductive effort of grouse. Integrating these technologies will allow researchers to better assess and manage the links among habitat quality (safety and food), resource acquisition (foraging behavior) and reproductive behaviors of grouse.

Large‐scale disturbances, such as megafires, motivate restoration at equally large extents. Measuring the survival and growth of individual plants plays a key role in current efforts to monitor restoration success. However, the scale of modern restoration (e.g., >10,000 ha) challenges measurements of demographic rates with field data. In this study, we demonstrate how unoccupied aerial system (UAS) flights can provide an efficient solution to the tradeoff of precision and spatial extent in detecting demographic rates from the air. We flew two, sequential UAS flights at two sagebrush (Artemisia tridentata) common gardens to measure the survival and growth of individual plants. The accuracy of Bayesian‐optimized segmentation of individual shrub canopies was high (73–95%, depending on the year and site), and remotely sensed survival estimates were within 10% of ground‐truthed survival censuses. Stand age structure affected remotely sensed estimates of growth; growth was overestimated relative to field‐based estimates by 57% in the first garden with older stands, but agreement was high in the second garden with younger stands. Further, younger stands (similar to those just after disturbance) with shorter, smaller plants were sometimes confused with other shrub species and bunchgrasses, demonstrating a need for integrating spectral classification approaches that are increasingly available on affordable UAS platforms. The older stand had several merged canopies, which led to an underestimation of abundance but did not bias remotely sensed survival estimates. Advances in segmentation and UAS structure from motion photogrammetry will enable demographic rate measurements at management‐relevant extents. [ABSTRACT FROM AUTHOR]

Understanding interactions between environmental stress and genetic variation is crucial to predict the adaptive capacity of species to climate change. Leaf temperature is both a driver and a responsive indicator of plant physiological response to thermal stress, and methods to monitor it are needed. Foliar temperatures vary across leaf to canopy scales and are influenced by genetic factors, challenging efforts to map and model this critical variable. Thermal imagery collected using unoccupied aerial systems (UAS) offers an innovative way to measure thermal variation in plants across landscapes at leaf‐level resolutions. We used a UAS equipped with a thermal camera to assess temperature variation among genetically distinct populations of big sagebrush (Artemisia tridentata), a keystone plant species that is the focus of intensive restoration efforts throughout much of western North America. We completed flights across a growing season in a sagebrush common garden to map leaf temperature relative to subspecies and cytotype, physiological phenotypes of plants, and summer heat stress. Our objectives were to (1) determine whether leaf‐level stomatal conductance corresponds with changes in crown temperature; (2) quantify genetic (i.e., subspecies and cytotype) contributions to variation in leaf and crown temperatures; and (3) identify how crown structure, solar radiation, and subspecies‐cytotype relate to leaf‐level temperature. When considered across the whole season, stomatal conductance was negatively, non‐linearly correlated with crown‐level temperature derived from UAS. Subspecies identity best explained crown‐level temperature with no difference observed between cytotypes. However, structural phenotypes and microclimate best explained leaf‐level temperature. These results show how fine‐scale thermal mapping can decouple the contribution of genetic, phenotypic, and microclimate factors on leaf temperature dynamics. As climate‐change‐induced heat stress becomes prevalent, thermal UAS represents a promising way to track plant phenotypes that emerge from gene‐by‐environment interactions. [ABSTRACT FROM AUTHOR]

Widely distributed plants of western North America experience divergent selection across environmental gradients, have complex histories shaped by biogeographic barriers and distributional shifts and often illustrate continuums of reproductive isolation. Rubber rabbitbrush (Ericameria nauseosa) is a foundational shrub species that occurs across diverse environments of western North America. Its remarkable phenotypic diversity is currently ascribed to two subspecies—Ericameria nauseosa nauseosa and Ericameria nauseosa consimilis—and 22 named varieties. To understand how genetic variation is partitioned across subspecies, varieties, and environments, we used high throughput sequencing of reduced representation libraries. We found clear evidence for divergence between the two subspecies, despite largely sympatric distributions. Numerous locations exhibiting admixed ancestry were not geographically localized but were widely distributed across a mosaic hybrid zone. The occurrence of hybrid and subspecific ancestries was strongly predicted by environmental variables as well as the proximity to major ecotones between ecoregions. Although this repeatability illustrates the importance of environmental factors in shaping reproductive isolation, variability in the prevalence of hybridization also indicates these factors likely differ across ecological contexts. There was mixed evidence for the evolutionary cohesiveness of varieties, but several genetically distinct and narrow endemic varieties exhibited admixed subspecific ancestries, hinting at the possibility for transgressive hybridization to contribute to phenotypic novelty and the colonization of new environments in E. nauseosa. [ABSTRACT FROM AUTHOR]

Establishing an effective restoration program requires baseline genetic information to make sound decisions for seed increase and transfer. For many plants this information is lacking, especially among native forbs that are critical for pollinator health. Erigeron speciosus is a widespread, perennial forb occupying montane environments in the western United States and Canada. This species is important in fostering pollinator diversity. Our study examines the population genetic patterns across the species range using reduced‐representation sequencing and surveys for genome duplication using flow cytometry and cytology. These genomic tools provide critical information for seed increase and seed transfer, necessary for restoration programs. Population genetic differentiation (FST) average was 0.13 and ranged from 0.05 to 0.24 among 23 collection sites. Model‐based Bayesian clustering supported a model with collection sites grouped into two populations, occupying distinct geographic regions of this species range. A genetic distance‐based neighbor‐joining tree also supported this division. Flow cytometry of 53 samples from 17 populations had 2C values that ranged from 1.7 to 3.6 pg with a mean 2C value of 2.3 pg. Putative triploids were found in two individuals from one collection site. The spatial distribution of genetic structure supports regionally based taxonomic descriptions of two varieties: speciosus in the North and macranthus in the South. This assessment of genetic structure and genome duplication describes an effective approach in developing baseline genetic information for restoration species, especially those species that may harbor complex taxonomy and polyploidy. [ABSTRACT FROM AUTHOR]

Coleogyne ramosissima Torr. (blackbrush) is a dominant xerophytic shrub species in the ecotone between the warm and cold deserts of interior western North America. Amplified fragment length polymorphisms (AFLPs) were used to survey genetic diversity and population genetic structure at 14 collection sites across the species range. Analysis revealed significant population differentiation ([F.sub.ST] = 0.103, p < 0.0001) and reasonably high levels of genetic diversity (expected heterozygosity; [H.sub.E] = 0.26), a surprising result for a putative paleoendemic species. Model-based Bayesian clustering, principal coordinates analysis, and neighbor-joining analysis all produced support for the existence of two metapopulations, the first centered on the Mojave Desert and the second on the Colorado Plateau. These genetic data, coupled with information from Late Pleistocene and Holocene packrat (genus Neotoma Say and Ord, 1825) middens, illustrate a demographic history in which eastern and western distributions were disjunct during the Last Glacial Maximum and remained so through the Holocene, forming the present-day metapopulations in the Mojave Desert and Colorado Plateau. This strong regional genetic differentiation has implications for population persistence and migration in response to future climate change, as well as for shrubland restoration following anthropogenic disturbances such as annual grass invasion and wildfire. Key words: amplified fragment length polymorphisms, biogeography, Colorado Plateau, Mojave, postglacial colonization. Coleogyne ramosissima Torr. (blackbrush) constitue une espece arbustive xerophyte de l'ecotone entre les deserts chauds et froids de l'interieur de l'ouest Nord-Americain. Les auteurs ont utilise les polymorphismes de la longueur des fragments amplifies (PFLAs) pour examiner la diversite genetique et la structure genetique des populations sur 14 sites de recolte distribues sur l'ensemble de l'aire de l'espece. Les analyses revelent une differenciation significative des populations ([F.sub.ST] = 0,103, p < 0,0001) ainsi que des degres relativement eleves de diversite genetique (heterozygosie attendue; [H.sub.E] = 0,26), un resultat surprenant pour une espece presumee paleoendemique. Une modelisation basee sur le regroupement bayesien, l'analyse des coordonnees principales et l'analyse des liaisons entre voisins (neighbor-joining analysis), toutes supportent l'existence de deux metapopulations, la premiere centree sur le Desert Mojave et la seconde sur le Plateau du Colorado. Ces donnees genetiques, couplees avec l'information provenant des monticules de detritus de rats du genre Neotoma Say and Ord, 1825, illustrent une histoire demographique dans laquelle les distributions orientales et occidentales se sont disjointes au cours du maximum de la derniere glaciation, pour demeurer telles quelles tout au long de l'Holocene, formant les metapopulations du Desert Mojave et du Plateau du Colorado. Cette forte differenciation genetique regionale a des implications pour la persistance des populations et leur migration en reaction au changement climatique future, ainsi que pour la restauration des arbustaies, suite aux perturbations anthropiques comme l'invasion par des graminees annuelles et les incendies. Mots-cles : polymorphismes des longueurs des fragments amplifies, biogeographies, Plateau du Colorado, Mojave, colonisation postglaciaire. [Traduit par la Redaction], Introduction Past climate change represented by the Last Glacial Maximum (LGM, ca. 25 000 to 13 000 year before present (BP)) followed by Holocene warming (ca. < 10 000 year [...]

Abstract: The white-pine blister rust fungus, Cronartium ribicola Fisch. in Rabenh., continues to spread in North America, utilizing various aecial (primary) and telial (alternate) hosts, some of which have only [...]

The rate of global climate change is projected to outpace the ability of many natural populations and species to adapt. Assisted migration (AM), which is defined as the managed movement of climate‐adapted individuals within or outside the species ranges, is a conservation option to improve species' adaptive capacity and facilitate persistence. Although conservation biologists have long been using genetic tools to increase or maintain diversity of natural populations, genomic techniques could add extra benefit in AM that include selectively neutral and adaptive regions of the genome. In this review, we first propose a framework along with detailed procedures to aid collaboration among scientists, agencies, and local and regional managers during the decision‐making process of genomics‐guided AM. We then summarize the genomic approaches for applying AM, followed by a literature search of existing incorporation of genomics in AM across taxa. Our literature search initially identified 729 publications, but after filtering returned only 50 empirical studies that were either directly applied or considered genomics in AM related to climate change across taxa of plants, terrestrial animals, and aquatic animals; 42 studies were in plants. This demonstrated limited application of genomic methods in AM in organisms other than plants, so we provide further case studies as two examples to demonstrate the negative impact of climate change on non‐model species and how genomics could be applied in AM. With the rapidly developing sequencing technology and accumulating genomic data, we expect to see more successful applications of genomics in AM, and more broadly, in the conservation of biodiversity. [ABSTRACT FROM AUTHOR]

Abstract Background Big sagebrush (Artemisia tridentata) is one of the most widely distributed and ecologically important shrub species in western North America. This species serves as a critical habitat and food resource for many animals and invertebrates. Habitat loss due to a combination of disturbances followed by establishment of invasive plant species is a serious threat to big sagebrush ecosystem sustainability. Lack of genomic data has limited our understanding of the evolutionary history and ecological adaptation in this species. Here, we report on the sequencing of expressed sequence tags (ESTs) and detection of single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers in subspecies of big sagebrush. Results cDNA of A. tridentata sspp. tridentata and vaseyana were normalized and sequenced using the 454 GS FLX Titanium pyrosequencing technology. Assembly of the reads resulted in 20,357 contig consensus sequences in ssp. tridentata and 20,250 contigs in ssp. vaseyana. A BLASTx search against the non-redundant (NR) protein database using 29,541 consensus sequences obtained from a combined assembly resulted in 21,436 sequences with significant blast alignments (≤ 1e-15). A total of 20,952 SNPs and 119 polymorphic SSRs were detected between the two subspecies. SNPs were validated through various methods including sequence capture. Validation of SNPs in different individuals uncovered a high level of nucleotide variation in EST sequences. EST sequences of a third, tetraploid subspecies (ssp. wyomingensis) obtained by Illumina sequencing were mapped to the consensus sequences of the combined 454 EST assembly. Approximately one-third of the SNPs between sspp. tridentata and vaseyana identified in the combined assembly were also polymorphic within the two geographically distant ssp. wyomingensis samples. Conclusion We have produced a large EST dataset for Artemisia tridentata, which contains a large sample of the big sagebrush leaf transcriptome. SNP mapping among the three subspecies suggest the origin of ssp. wyomingensis via mixed ancestry. A large number of SNP and SSR markers provide the foundation for future research to address questions in big sagebrush evolution, ecological genetics, and conservation using genomic approaches.