Dr. Lesley DeFalco is a Plant Ecologist with the U.S. Geological Survey's Western Ecological Research Center.
RESEARCH INTERESTS
- Restoration of Aridlands
- Conservation biology
- Desert Community Ecology
- Ecological monitoring
- Effects of Anthropogenic Disturbance
- Evaluation of management
- Fire ecology
- Global climate change
- Invasive species ecology
- Physiological plant ecology
- Plant ecology
- Species interactions
- Threatened and endangered species
EDUCATION
PhD, Ecology, Evolution & Conservation Biology, University of Nevada, Reno, NV 2003
MS, Botany, Colorado State University, Fort Collins, CO 1995
BS, Biological Sciences, Colorado State University, Fort Collins, CO 1989
COMMITTEES
- Botanical Society of America
- California Native Plant Society (Mojave Chapter)
- Ecological Society of America
- Nevada Native Plant Society
- Society for Ecological Restoration (Southwest Chapter)
Science and Products
WERC Fire Science
WERC scientists are defining the past, present, and future of wildfires for wildlife and human communities. Explore this webpage to learn about specific, ongoing projects across California and parts of Nevada.
Process-based Approaches for Ecological Restoration of Degraded Drylands
Surface disturbances ranging from military training, recreation, energy exploration and development, and wildfires impact a large majority of federal lands in the western US, but the ecological and economic impacts are poorly understood. Explore this webpage to learn how Dr. Lesley DeFalco and her research team are currently evaluating and refining conventional approaches for post-fire restoration...
Native Plant Materials for Ecological Restoration of Degraded Drylands
There is a growing consensus among resource managers to use native plant materials for ecological restoration of degraded drylands. Some plant species may be suitable for re-introduction across broad environmental gradients. Other species may fail under narrower conditions, or their re-introduction may have genetic consequences for local ecotypes, particularly when adapting to future climate...
Conservation of Rare, Sensitive, and At-risk Desert Plant Species
The Mojave Desert is among the hottest and driest of the North American drylands, but in spite of these extreme conditions, and in part because of them, a diverse flora exists. This diversity of rare, endemic, and endangered species is threatened by the complex interaction between fluctuating climate and human-mediated disturbances. USGS studies have identified rare species “hotspots” for planning...
Southwest Energy Exploration, Development, and Reclamation (SWEDR)
Deserts of the southwestern US are replete with oil and gas deposits as well as sites for solar, wind, and geothermal energy production. In the past, many of these resources have been too expensive to develop, but increased demand and new technologies have led to an increase in exploration and development. However, desert ecosystems generally have low resilience to disturbance. More frequent...
Boulder City Field Station
The Boulder City Field Station supports research scientists leading projects in desert ecosystem restoration, genetics of iconic trees of the Mojave Desert, predator-prey studies on protected lands, and more. Select the next tab for a comprehensive summary of studies at this site.
Species Distribution Models for Native Species in the Mojave Desert
Preserving native species diversity is fundamental to ecosystem conservation. Selecting appropriate native species for use in restoration is a critical component of project design and may emphasize species attributes such as life history, functional type, pollinator services, and nutritional value for wildlife. Determining which species are likely to establish and persist in a particular environme
Ecotypic Variation in Ambrosia dumosa and Larrea tridentata from Three Sites Across the Mojave (2014 - 2018)
These data were acquired from two native Mojave Desert species, Ambrosia dumosa and Larrea tridentata, from 3 sites (50 m x 50 m garden plots) distributed across the differing Mojave Desert ecotones. These sites were located on the Fort Irwin National Training Center (CA), north of Joshua Tree National Park (CA), and north of Saint George (UT). Growth and survivorship data were collected monthly f
Genetic and Habitat Data for Plantago ovata in the Mojave Desert
These datasets were developed to represent the genetic diversity, population structure, and geographic distribution of Plantago ovata in the Mojave Desert. This data release consists of two tab-delimited text files representing the genetic diversity and structure of Plantago ovata (.genepop and .vcf), and two raster spatial datasets (GeoTIFF) reflecting predicted habitat for the species within the
Principal components of climate variation in the Desert Southwest (ver. 2.0, September 2019)
Five principal components are used to represent the climate variation in an original set of 12 climate variables reflecting precipitation and temperature gradients. The dataset provides coverage for four regions (the Sonoran Desert, Mojave Desert, Colorado Plateau, and Southern Great Basin) and three time periods including current climate (defined as the 1980-2010 normal period) and future climate
Principal components of climate variation in the Desert Southwest for the time periods 1980-2010, 2040-2070 (RCP8.5) and (RCP4.5)
Five principal components are used to represent the climate variation in an original set of 12 climate variables reflecting precipitation and temperature gradients. The dataset provides coverage for four regions (the Sonoran Desert, Mojave Desert, Colorado Plateau, and Southern Great Basin) and two time periods: current climate (defined as the 1980-2010 normal period) and future climate (defined a
Filter Total Items: 40
Soil medium and watering frequency alter growth and allocation for Blue Diamond cholla (Cylindropuntia multigeniculata), a rare cactus of the northeast Mojave Desert, USA
Blue Diamond cholla (Cylindropuntia multigeniculata (Clokey) Blackb. [Cactaceae]) is a rare cactus of the Mojave Desert. We explored whether cultivation from joint cuttings is a viable method for supporting threatened populations. Terminal joints were collected from adult plants at the type locality and grown in a shade house: We tested whether 2 soil mixes that varied in the ratio of inorganic an
Authors
Sara J. Scoles-Sciulla, Alexander Stosich, Lesley A. DeFalco
A review of Arctomecon californica (Papaveraceae) with a focus on the species’ potential for propagation and reintroduction and conservation needs
Las Vegas bearpoppy (Arctomecon californica) occurrences have fluctuated during the past several decades, in part due to interannual variability in rainfall that influences recruitment and mortality events; yet, development in the Las Vegas Valley continues to threaten habitat supporting this species. Arctomecon californica was petitioned for listing under the Endangered Species Act in 2019 and is
Authors
Alexander Stosich, Lesley A. DeFalco, Sara J. Scoles-Sciulla
What common-garden experiments tell us about climate responses in plants
Common garden experiments are indoor or outdoor plantings of species or populations collected from multiple distinct geographic locations, grown together under shared conditions. These experiments examine a range of questions for theory and application using a variety of methods for analysis. The eight papers of this special feature comprise a cross section of contemporary approaches, summarized a
Authors
Susanne Schwinning, Christopher J. Lorti, Todd C. Esque, Lesley A. DeFalco
Seed menus: An integrated decision-support framework for native plant restoration in the Mojave Desert
The combination of ecosystem stressors, rapid climate change, and increasing landscape-scale development has necessitated active restoration across large tracts of disturbed habitats in the arid southwestern United States. In this context, programmatic directives such as the National Seed Strategy for Rehabilitation and Restoration have increasingly emphasized improved restoration practices that p
Authors
Daniel F. Shryock, Lesley A. DeFalco, Todd C. Esque
Protocol for route restoration in California’s desert renewable energy conservation plan area
In the deserts of the Southwestern United States, increased off-highway vehicle use can lead to widespread vehicular damage to desert ecosystems. As the popularity and intensity of vehicle use on public lands continues, the Bureau of Land Management (BLM) is challenged to manage the routes used by recreationists while minimizing activity beyond designated routes and mitigating environmental impact
Authors
Todd C. Esque, Ka-Voka R. Jackson, Alexandrea M. Rice, Jeffery K. Childers, Caroline S. Woods, Amy Fesnock-Parker, Andrew C. Johnson, Lauren J. Price, Kristin E. Forgrave, Sara J. Scoles-Sciulla, Lesley A. DeFalco
Local climate adaptations in two ubiquitous Mojave Desert shrub species, Ambrosia dumosa and Larrea tridentata
Widely distributed species are often locally adapted to climate gradients across their ranges. But little is known about the patterns of intraspecific adaptation in desert shrubs.We examined the questions of local adaptation in multiple populations of two common shrub species of the winter-wet Mojave Desert in North America in a multiple common garden experiment. Plants were raised in the greenhou
Authors
Nathan A. Custer, Susan Schwinning, Lesley A. DeFalco, Todd C. Esque
Priority species lists to restore desert tortoise and pollinator habitats in Mojave Desert shrublands
Mojave Desert shrublands are home to unique plants and wildlife and are experiencing rapid habitat change due to unprecedented large-scale disturbances; yet, established practices to effectively restore disturbed landscapes are not well developed. A priority species list of native plant taxa was developed to guide seed collectors, commercial growers, resource managers, and restoration practitioner
Authors
Todd C. Esque, Lesley A. DeFalco, Gayle Loren Tyree, K. Kristina Drake, Kenneth E. Nussear, Joseph S Wilson
Harnessing landscape genomics to identify future climate resilient genotypes in a desert annual
Local adaptation features critically in shaping species responses to changing environments, complicating efforts to revegetate degraded areas. Rapid climate change poses an additional challenge that could reduce fitness of even locally sourced seeds in restoration. Predictive restoration strategies that apply seeds with favourable adaptations to future climate may promote long‐term resilience. Lan
Authors
Daniel F. Shryock, Loraine K Washburn, Lesley A. DeFalco, Todd C. Esque
Spatial decision‐support tools to guide restoration and seed‐sourcing in the Desert Southwest
Altered disturbance regimes and shifting climates have increased the need for large‐scale restoration treatments across the western United States. Seed‐sourcing remains a considerable challenge for revegetation efforts, particularly on public lands where policy favors the use of native, locally sourced plant material to avoid maladaptation. An important area of emphasis for public agencies has bee
Authors
Daniel F. Shryock, Lesley A. DeFalco, Todd C. Esque
Drawing a line in the sand: Effectiveness of off-highway vehicle management in California's Sonoran desert
Public land policies manage multiple uses while striving to protect vulnerable plant and wildlife habitats from degradation; yet the effectiveness of such policies are infrequently evaluated, particularly for remote landscapes that are difficult to monitor. We assessed the use and impacts of recreational vehicles on Mojave Desert washes (intermittent streams) in the Chemehuevi Desert Wildlife Mana
Authors
Nathan Custer, Lesley A. Defalco, Kenneth E. Nussear, Todd C. Esque
The role of salinity tolerance and competition in the distribution of an endangered desert salt marsh endemic
Rare plants are often associated with distinctive soil types, and understanding why endemic species occur in unique environments is fundamental for their management. At Ash Meadows National Wildlife Refuge in southern Nevada, USA, we evaluated whether the limited distribution of endangered Amargosa niterwort (Nitrophila mohavensis) is explained by this species’ tolerance of saline soils on salt-en
Authors
Lesley A. DeFalco, Sara J. Scoles-Sciulla, Emily R. Beamguard
Landscape genetic approaches to guide native plant restoration in the Mojave Desert
Restoring dryland ecosystems is a global challenge due to synergistic drivers of disturbance coupled with unpredictable environmental conditions. Dryland plant species have evolved complex life-history strategies to cope with fluctuating resources and climatic extremes. Although rarely quantified, local adaptation is likely widespread among these species and potentially influences restoration outc
Authors
Daniel F. Shryock, Caroline A. Havrilla, Lesley A. DeFalco, Todd C. Esque, Nathan Custer, Troy E. Wood
Mojave Seed Menus: a new spatial tool for restoration software release v1.0
Mojave Seed Menus is a spatial decision-support tool designed to
help land managers create suitable seed mixes for restoration sites,
such as a burned area or other mapped spatial feature. The application
provides coverage for the Mojave Desert ecoregion.
Seed menus are based on a combination of habitat suitability models for
50 priority restoration plant species. Species are selected based on
the
Science and Products
- Science
WERC Fire Science
WERC scientists are defining the past, present, and future of wildfires for wildlife and human communities. Explore this webpage to learn about specific, ongoing projects across California and parts of Nevada.Process-based Approaches for Ecological Restoration of Degraded Drylands
Surface disturbances ranging from military training, recreation, energy exploration and development, and wildfires impact a large majority of federal lands in the western US, but the ecological and economic impacts are poorly understood. Explore this webpage to learn how Dr. Lesley DeFalco and her research team are currently evaluating and refining conventional approaches for post-fire restoration...Native Plant Materials for Ecological Restoration of Degraded Drylands
There is a growing consensus among resource managers to use native plant materials for ecological restoration of degraded drylands. Some plant species may be suitable for re-introduction across broad environmental gradients. Other species may fail under narrower conditions, or their re-introduction may have genetic consequences for local ecotypes, particularly when adapting to future climate...Conservation of Rare, Sensitive, and At-risk Desert Plant Species
The Mojave Desert is among the hottest and driest of the North American drylands, but in spite of these extreme conditions, and in part because of them, a diverse flora exists. This diversity of rare, endemic, and endangered species is threatened by the complex interaction between fluctuating climate and human-mediated disturbances. USGS studies have identified rare species “hotspots” for planning...Southwest Energy Exploration, Development, and Reclamation (SWEDR)
Deserts of the southwestern US are replete with oil and gas deposits as well as sites for solar, wind, and geothermal energy production. In the past, many of these resources have been too expensive to develop, but increased demand and new technologies have led to an increase in exploration and development. However, desert ecosystems generally have low resilience to disturbance. More frequent...Boulder City Field Station
The Boulder City Field Station supports research scientists leading projects in desert ecosystem restoration, genetics of iconic trees of the Mojave Desert, predator-prey studies on protected lands, and more. Select the next tab for a comprehensive summary of studies at this site. - Data
Species Distribution Models for Native Species in the Mojave Desert
Preserving native species diversity is fundamental to ecosystem conservation. Selecting appropriate native species for use in restoration is a critical component of project design and may emphasize species attributes such as life history, functional type, pollinator services, and nutritional value for wildlife. Determining which species are likely to establish and persist in a particular environmeEcotypic Variation in Ambrosia dumosa and Larrea tridentata from Three Sites Across the Mojave (2014 - 2018)
These data were acquired from two native Mojave Desert species, Ambrosia dumosa and Larrea tridentata, from 3 sites (50 m x 50 m garden plots) distributed across the differing Mojave Desert ecotones. These sites were located on the Fort Irwin National Training Center (CA), north of Joshua Tree National Park (CA), and north of Saint George (UT). Growth and survivorship data were collected monthly fGenetic and Habitat Data for Plantago ovata in the Mojave Desert
These datasets were developed to represent the genetic diversity, population structure, and geographic distribution of Plantago ovata in the Mojave Desert. This data release consists of two tab-delimited text files representing the genetic diversity and structure of Plantago ovata (.genepop and .vcf), and two raster spatial datasets (GeoTIFF) reflecting predicted habitat for the species within thePrincipal components of climate variation in the Desert Southwest (ver. 2.0, September 2019)
Five principal components are used to represent the climate variation in an original set of 12 climate variables reflecting precipitation and temperature gradients. The dataset provides coverage for four regions (the Sonoran Desert, Mojave Desert, Colorado Plateau, and Southern Great Basin) and three time periods including current climate (defined as the 1980-2010 normal period) and future climatePrincipal components of climate variation in the Desert Southwest for the time periods 1980-2010, 2040-2070 (RCP8.5) and (RCP4.5)
Five principal components are used to represent the climate variation in an original set of 12 climate variables reflecting precipitation and temperature gradients. The dataset provides coverage for four regions (the Sonoran Desert, Mojave Desert, Colorado Plateau, and Southern Great Basin) and two time periods: current climate (defined as the 1980-2010 normal period) and future climate (defined a - Publications
Filter Total Items: 40
Soil medium and watering frequency alter growth and allocation for Blue Diamond cholla (Cylindropuntia multigeniculata), a rare cactus of the northeast Mojave Desert, USA
Blue Diamond cholla (Cylindropuntia multigeniculata (Clokey) Blackb. [Cactaceae]) is a rare cactus of the Mojave Desert. We explored whether cultivation from joint cuttings is a viable method for supporting threatened populations. Terminal joints were collected from adult plants at the type locality and grown in a shade house: We tested whether 2 soil mixes that varied in the ratio of inorganic anAuthorsSara J. Scoles-Sciulla, Alexander Stosich, Lesley A. DeFalcoA review of Arctomecon californica (Papaveraceae) with a focus on the species’ potential for propagation and reintroduction and conservation needs
Las Vegas bearpoppy (Arctomecon californica) occurrences have fluctuated during the past several decades, in part due to interannual variability in rainfall that influences recruitment and mortality events; yet, development in the Las Vegas Valley continues to threaten habitat supporting this species. Arctomecon californica was petitioned for listing under the Endangered Species Act in 2019 and isAuthorsAlexander Stosich, Lesley A. DeFalco, Sara J. Scoles-SciullaWhat common-garden experiments tell us about climate responses in plants
Common garden experiments are indoor or outdoor plantings of species or populations collected from multiple distinct geographic locations, grown together under shared conditions. These experiments examine a range of questions for theory and application using a variety of methods for analysis. The eight papers of this special feature comprise a cross section of contemporary approaches, summarized aAuthorsSusanne Schwinning, Christopher J. Lorti, Todd C. Esque, Lesley A. DeFalcoSeed menus: An integrated decision-support framework for native plant restoration in the Mojave Desert
The combination of ecosystem stressors, rapid climate change, and increasing landscape-scale development has necessitated active restoration across large tracts of disturbed habitats in the arid southwestern United States. In this context, programmatic directives such as the National Seed Strategy for Rehabilitation and Restoration have increasingly emphasized improved restoration practices that pAuthorsDaniel F. Shryock, Lesley A. DeFalco, Todd C. EsqueProtocol for route restoration in California’s desert renewable energy conservation plan area
In the deserts of the Southwestern United States, increased off-highway vehicle use can lead to widespread vehicular damage to desert ecosystems. As the popularity and intensity of vehicle use on public lands continues, the Bureau of Land Management (BLM) is challenged to manage the routes used by recreationists while minimizing activity beyond designated routes and mitigating environmental impactAuthorsTodd C. Esque, Ka-Voka R. Jackson, Alexandrea M. Rice, Jeffery K. Childers, Caroline S. Woods, Amy Fesnock-Parker, Andrew C. Johnson, Lauren J. Price, Kristin E. Forgrave, Sara J. Scoles-Sciulla, Lesley A. DeFalcoLocal climate adaptations in two ubiquitous Mojave Desert shrub species, Ambrosia dumosa and Larrea tridentata
Widely distributed species are often locally adapted to climate gradients across their ranges. But little is known about the patterns of intraspecific adaptation in desert shrubs.We examined the questions of local adaptation in multiple populations of two common shrub species of the winter-wet Mojave Desert in North America in a multiple common garden experiment. Plants were raised in the greenhouAuthorsNathan A. Custer, Susan Schwinning, Lesley A. DeFalco, Todd C. EsquePriority species lists to restore desert tortoise and pollinator habitats in Mojave Desert shrublands
Mojave Desert shrublands are home to unique plants and wildlife and are experiencing rapid habitat change due to unprecedented large-scale disturbances; yet, established practices to effectively restore disturbed landscapes are not well developed. A priority species list of native plant taxa was developed to guide seed collectors, commercial growers, resource managers, and restoration practitionerAuthorsTodd C. Esque, Lesley A. DeFalco, Gayle Loren Tyree, K. Kristina Drake, Kenneth E. Nussear, Joseph S WilsonHarnessing landscape genomics to identify future climate resilient genotypes in a desert annual
Local adaptation features critically in shaping species responses to changing environments, complicating efforts to revegetate degraded areas. Rapid climate change poses an additional challenge that could reduce fitness of even locally sourced seeds in restoration. Predictive restoration strategies that apply seeds with favourable adaptations to future climate may promote long‐term resilience. LanAuthorsDaniel F. Shryock, Loraine K Washburn, Lesley A. DeFalco, Todd C. EsqueSpatial decision‐support tools to guide restoration and seed‐sourcing in the Desert Southwest
Altered disturbance regimes and shifting climates have increased the need for large‐scale restoration treatments across the western United States. Seed‐sourcing remains a considerable challenge for revegetation efforts, particularly on public lands where policy favors the use of native, locally sourced plant material to avoid maladaptation. An important area of emphasis for public agencies has beeAuthorsDaniel F. Shryock, Lesley A. DeFalco, Todd C. EsqueDrawing a line in the sand: Effectiveness of off-highway vehicle management in California's Sonoran desert
Public land policies manage multiple uses while striving to protect vulnerable plant and wildlife habitats from degradation; yet the effectiveness of such policies are infrequently evaluated, particularly for remote landscapes that are difficult to monitor. We assessed the use and impacts of recreational vehicles on Mojave Desert washes (intermittent streams) in the Chemehuevi Desert Wildlife ManaAuthorsNathan Custer, Lesley A. Defalco, Kenneth E. Nussear, Todd C. EsqueThe role of salinity tolerance and competition in the distribution of an endangered desert salt marsh endemic
Rare plants are often associated with distinctive soil types, and understanding why endemic species occur in unique environments is fundamental for their management. At Ash Meadows National Wildlife Refuge in southern Nevada, USA, we evaluated whether the limited distribution of endangered Amargosa niterwort (Nitrophila mohavensis) is explained by this species’ tolerance of saline soils on salt-enAuthorsLesley A. DeFalco, Sara J. Scoles-Sciulla, Emily R. BeamguardLandscape genetic approaches to guide native plant restoration in the Mojave Desert
Restoring dryland ecosystems is a global challenge due to synergistic drivers of disturbance coupled with unpredictable environmental conditions. Dryland plant species have evolved complex life-history strategies to cope with fluctuating resources and climatic extremes. Although rarely quantified, local adaptation is likely widespread among these species and potentially influences restoration outcAuthorsDaniel F. Shryock, Caroline A. Havrilla, Lesley A. DeFalco, Todd C. Esque, Nathan Custer, Troy E. Wood - Software
Mojave Seed Menus: a new spatial tool for restoration software release v1.0
Mojave Seed Menus is a spatial decision-support tool designed to help land managers create suitable seed mixes for restoration sites, such as a burned area or other mapped spatial feature. The application provides coverage for the Mojave Desert ecoregion. Seed menus are based on a combination of habitat suitability models for 50 priority restoration plant species. Species are selected based on the - News