Ehren Moler

James Madison University | JMU · School of Integrated Sciences

As the demand for drought hardy tree seedlings rises alongside global temperatures, there is a need to optimize nursery drought preconditioning methods to improve field performance of planted seedlings. This perspective article advocates for a more holistic approach to drought preconditioning research that considers the moderating role of plant dev...

Climate change is increasing the frequency and intensity of drought in the western USA. Evidence suggests that drought preconditioning of plants may improve the survival of planted seedlings under dry conditions through enhanced water uptake by roots, but the mechanisms underlying enhanced survival under drought remain unknown. We tested whether th...

Variation in gene expression among natural populations are key contributors to adaptive evolution. Understanding the architecture underlying adaptive trait evolution provides insights into the adaptive potential of populations exposed to novel selective pressures. We investigated patterns and processes driving trait differentiation under novel clim...

Background Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and...

Seedling emergence, survival, morphological and physiological traits, and oxidative stress resistance of southwestern white pine (Pinus strobiformis Engelm.) were studied in response to warming treatments applied during embryogenesis, germination, and early seedling growth. Daytime air temperature surrounding cones in tree canopies was warmed by +2...

Natural plant populations often exhibit marked differences in gene expression patterns that can reflect heterogeneity in selective pressures. Analyzing gene expression as a quantitative trait provides a unique opportunity to evaluate the underlying genomic basis of a plethora of traits and their interactions in driving adaptive evolution. We invest...

Establishment and retention of native plant communities in Southern California is challenged by increasing aridity and incidence of non native plant invasion and wildfire 5 . Rapid and lower cost methods of artificial plant regeneration, such as direct seeding and seedling outplanting , are needed to meet the demand for ecological restoration in in...

Contribution to the Canadian Forest Genetics Association Tree Seed Working Group reporting past, current, and projected future challenges to conifer tree seed collection in western North America.

Root system growth dynamics and architecture influence the establishment and field performance of planted forest tree seedlings. Roots display extensive phenotypic plasticity in response to changes in environmental conditions, which can be harnessed through management to produce seedlings with desirable root traits for better field performance. Thi...

Plant endosymbionts (endophytes) influence host plant health and express genotype-dependent ecological relationships with plant hosts. A fungal species intended to confer host plant resistance to a forest pathogen was used as inoculum to test for effects of inoculation on disease resistance, microbiomes, and phytochemistry of a threatened pine spec...

We reviewed approaches for combining genetic and cultural tools to solve challenges associated with the improvement of tree seedling root systems for enhanced survival and growth. Literature regarding sources of variation in root traits, relationships between root traits and seedling growth and survival, and root trait heritability estimates from p...

Bromus tectorum poses a substantial threat to sagebrush steppe in the North American intermountain west. Responses of B. tectorum to increasing aridity across the western USA may influence the species’ ability to invade new habitats and further dominate colonised regions. We investigated the phenotypic plasticity of stomatal density, root and shoot...

Background Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and...

Background Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and...

Citizen science use in common garden experiments

Southwestern white pine (Pinus strobiformis; SWWP) is a native tree species threatened by the rapidly changing climate and a non-native tree disease (white pine blister rust). Our team of researchers studies the ecology and evolution of SWWP across its range in the United States and Mexico to find solutions for sustaining this tree. Genetic and env...

Ecophysiological measures of plant water use were measured across Pinus strobiformis seedlings replicated across two warming treatments: 1) warmed versus control cone warming treatments during the final summer of seed development, and 2) three temperatures imposed during the first four months of seedling growth.

Chlorophyll a fluorescence of PSII and foliar temperature investigated following controlled environmental warming during: (1) seed development, and (2) first four months of seedling growth.

Ecophysiological responses of southwestern white pine (P. strobiformis) to controlled temperature manipulations during both seed development and the first four months of seedling growth. Bulk modulus of elasticity and turgor loss point were differentially responsive to temperature treatments depending on the timing of temperature manipulation. We c...

Ecophysiological responses of southwestern white pine (P. strobiformis) to controlled temperature manipulations during both seed development and the first four months of seedling growth. Bulk modulus of elasticity and turgor loss point were differentially responsive to temperature treatments depending on the timing of temperature manipulation. We c...

Advances in chromatin state mapping, high-throughput DNA sequencing, and bioinformatics have revolutionized the study and interpretability of epigenomic variation. The increasing feasibility of obtaining and analyzing detailed information on epigenetic mechanisms across many individuals and populations has enabled the study of epigenomic variation...

We present an assessment of relationships between correlates, signs, and symptoms of white pine blister rust and fungal endophyte communities of whitebark pine (Pinus albicaulis) foliage in the southern Cascade Range, OR, USA. Parsimonious combinations of historically important predictors of blister rust provided effective logistic models (AUC = 0....

This poster describes results of a brief greenhouse experiment designed to understand how the physiology and morphology of 6-month old southwestern white pine (P. strobiformis) seedlings is influenced by controlled drought and warming.