David A Pyke
Biography
Education
Ph.D. Botany, 1983, Washington State University
M.S. Forest and Range Management, 1977, Washington State University
B.S. Range Management (Wildlife option), 1976, Washington State University
Specialty
Plant ecology, restoration ecology, monitoring and assessments of ecosystem status of rangelands (grassland, shrublands and savannas)
Research Interests
Population ecology of native and invasive plants in the Intermountain West. Monitoring protocols for ecosystem integrity on wild lands. Restoration ecology of native plants on disturbed and invaded lands.
Personal Interests
Skiing, Cycling, Baseball, Softball, Gardening, & Beer Brewing
Background
Former Assistant Center Director of FRESC 1996-1999
Science and Products
Cheatgrass and Medusahead
Invasive annual grasses, such as cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae), are one of the most significant stressors to rangeland ecosystems in the western U.S. Their expansion and dominance across this area are the most damaging ecosystem agents on this iconic landscape.
Standardized Emergency Stabilization and Rehabilitation Monitoring Protocols (ES&R)
Fire rehabilitation programs have existed within federal agencies since the early 1960s. The U.S. Forest Service and Bureau of Land Management are the largest users of emergency stabilization and rehabilitation (ES&R) funds, but these agencies only sporadically implement proposed monitoring and rarely use common protocols. As a result, it is impossible to draw scientifically credible...
Restoration and Ecology of Arid Lands Team (FRESC)
The focus of our research is on the restoration and monitoring of the plants and soils of the Intermountain West. Our lab is part of the Snake River Field Station, but is located in Corvallis, Oregon. Research topics include fire rehabilitation effects and effectiveness, indicators of rangeland health, invasive species ecology, and restoration of shrub steppe ecosystems.
Restoration of Shrub Steppe Ecosystems
This research theme provides land managers information to help them make restoration decision at local and landscape scales.
Invasive Species Ecology
Invasive annual grasses are the greatest threat to shrub-grassland ecosystems of the Intermountain West. These grasses grow earlier in the season than native plants, usurping water and nutrients, and making survival and reproduction difficult for native species. They also change the fire regime within the ecosystem, creating more frequent and larger wildfires. We are attempting to understand...
Indicators of Rangeland Health
Rangelands are natural ecosystems where the native vegetation consists predominantly of grasses, grass-like plants, forbs, or shrubs. Rangelands include natural grasslands, savannas, shrublands, oak and pinyon-juniper woodlands, many deserts, tundra, alpine communities, marshes, and wet meadows.
Fire Rehabilitation Effects and Effectiveness
Mitigation of ecological damage caused by rangeland wildfires focuses on conservation of ecosystem function through reducing soil erosion and spread of invasive plants. The overall effectiveness of these treatments is variable, and their necessity has been debated recently. We conduct research projects and synthesize findings to determine if mitigation treatments: 1) protect ecosystems against...
Climate change and ecohydrology in temperate dryland ecosystems: a global assessment
Water cycling and availability exert dominant control over ecological processes and the sustainability of ecosystem services in water - limited ecosystems. Consequently, dryland ecosystems have the potential to be dramatically impacted by hydrologic alterations emerging from global change, notably increasing temperature and altered precipitation patterns. In addition, the possibility of...
Compilation of BLM Monitoring Reports Assessing Post Wildfire Seeding of Rangelands, 2001-2009
We reviewed closeout reports from 2001-2009 to conduct a meta-analysis of seeding after wildfires to determine if seedings may (1) protect ecosystems against soil erosion and (2) reduce invasion or abundance of undesirable nonnative plant species.
Compilation of Studies Assessing Post Wildfire Seeding of Rangelands Worldwide, 1965-2010
We reviewed literature from 1965-2010 to conduct a meta-analysis of seeding after wildfires to determine if seedings may (1) protect ecosystems against soil erosion and (2) reduce invasion or abundance of undesirable nonnative plant species.
Interpreting Indicators of Rangeland Health, Version 5: Bureau of Land Management Technical Reference 1734-6
The Interpreting Indicators of Rangeland Health (IIRH) protocol is designed for assessing ecosystem function on rangelands and woodlands. The protocol was developed by an interagency cadre of technical experts and has been in use by for two decades. The protocol is well accepted and is a valuable tool for communicating rangeland conditions with...
Pellant, Mike; Shaver, Patrick L; Pyke, David A.; Herrick, Jeffrey E.; Lepak, Nika; Riegel, Gregg; Kachergis, Emily; Newingham, Beth A.; Toledo, David; Busby, Frank EPostfire growth of seeded and planted big sagebrush - Strategic designs for restoring Greater Sage-grouse nesting habitat
Wildfires change plant community structure and impact wildlife habitat and population dynamics. Recent wildfire‐induced losses of big sagebrush (Artemisia tridentata) in North American shrublands are outpacing natural recovery and leading to substantial losses in habitat for sagebrush‐obligate species such as Greater Sage‐grouse. Managers are...
Pyke, David A.; Shriver, Robert K.; Arkle, Robert; Pilliod, David; Aldridge, Cameron L.; Coates, Peter S.; Germino, Matthew; Heinrichs, Julie Arlene; Ricca, Mark A.; Shaff, ScottBiological soil crusts in ecological restoration: Emerging research and perspectives
Drylands encompass over 40% of terrestrial ecosystems and face significant anthropogenic degradation causing a loss of ecosystem integrity, services, and deterioration of social‐ecological systems. To combat this degradation, some dryland restoration efforts have focused on the use of biological soil crusts (biocrusts): complex communities of...
Antoninka, Anita; Faist, Akasha M.; Rodriguez-Caballero, Emilio; Young, Kristina E; Chaudhary, V Bala; Condon, Lea A.; Pyke, David A.Weed-suppressive bacteria applied as a spray or seed mixture did not control Bromus tectorum
We conducted two case studies testing effectiveness of a soil-borne bacteria, Pseudomonas fluorescens strain D7, in controlling Bromus tectorum (cheatgrass) and in affecting the density of sown desirable seedlings. We conducted two case studies testing D7’s ability to control of B. tectorum (cover, biomass and density) when mixed with native seeds...
Pyke, David A.; Shaff, Scott; Gregg, Michael A; Conley, Julie L.Context-dependent effects of livestock grazing in deserts of western North America
This chapter provides a general review of grazing disturbance by large mammalian grazers and the role of ecological context in moderating its effects, with emphasis on North American deserts. It discusses the ecological consequences of cessation of livestock grazing and present a case study from the Mojave Desert, United States of America. A...
Veblen, Kari E.; Beever, Erik A.; Pyke, David A.Hydroseeding tackifiers and dryland moss restoration potential
Tackifiers are long‐chain carbon compounds used for soil stabilization and hydroseeding and could provide a vehicle for biological soil crust restoration. We examined the sensitivity of two dryland mosses, Bryum argenteum and Syntrichia ruralis, to three common tackifiers ‐ guar, psyllium, and polyacrylamide (PAM) ‐ at 0.5x, 1....
W. Dillon Blankenship; Condon, Lea A.; Pyke, David A.Transient population dynamics impede restoration and may promote ecosystem transformation after disturbance
The apparent failure of ecosystems to recover from increasingly widespread disturbance is a global concern. Despite growing focus on factors inhibiting resilience and restoration, we still know very little about how demographic and population processes influence recovery. Using inverse and forward demographic modelling of 531 post‐fire sagebrush...
Shriver, Robert K.; Andrews, Caitlin M.; Arkle, Robert; Barnard, David; Duniway, Michael C.; Germino, Matthew J.; Pilliod, David S.; Pyke, David A.; Welty, Justin; Bradford, John B.Adaptive Management and Monitoring
This is a chapter in a technical report that is the second of two works describing longer-term actions to implement policies and strategies for preventing and suppressing rangeland fire and restoring rangeland landscapes affected by fire in the Western United States. The first part, Chambers et al 2017, "Science Framework for conservation and...
Wiechman, Lief A.; Pyke, David A.; Crist, Michele R.; Munson, Seth; Brooks, Matthew; Chambers, Jeanne C.; Rowland, Mary M.; Kachergis, Emily J; Davidson, ZoeA strategy for defining the reference for land health and degradation assessments
Much of the confusion about the definition of reference conditions for land health and degradation assessments is due to differences in policy and management objectives. Selection of a historic reference where it is not necessary, such as in the definition of future land degradation neutrality, can add significant cost and uncertainty to land...
Herrick, Jeffrey E.; Shaver, Patrick; Pyke, David A.; Pellant, Mike; Toledo, David; Lepak, NikaAdapting management to a changing world: Warm temperatures, dry soil, and interannual variability limit restoration success of a dominant woody shrub in temperate drylands
Restoration and rehabilitation of native vegetation in dryland ecosystems, which encompass over 40% of terrestrial ecosystems, is a common challenge that continues to grow as wildfire and biological invasions transform dryland plant communities. The difficulty in part stems from low and variable precipitation, combined with limited understanding...
Shriver, Robert K.; Andrews, Caitlin M.; Pilliod, David S.; Arkle, Robert; Welty, Justin; Germino, Matthew J.; Duniway, Michael C.; Pyke, David A.; Bradford, John B.Resiliency of biological soil crusts and vascular plants varies among morphogroups with disturbance intensity
Background and aimsDisturbance affects the ability of organisms to persist on a site, and disturbance history acts as a filter of community composition. This is true for vascular plants and morphological groups of biocrusts, which respond differently to disturbance. Although functioning arid ecosystems include both groups, filtering of...
Condon, Lea A.; Pyke, David A.Resilience and resistance in sagebrush ecosystems are associated with seasonal soil temperature and water availability
Invasion and dominance of exotic grasses and increased fire frequency threaten native ecosystems worldwide. In the Great Basin region of the western United States, woody and herbaceous fuel treatments are implemented to decrease the effects of wildfire and increase sagebrush (Artemisia spp.) ecosystem resilience to disturbance and resistance...
Roundy, Bruce A.; Chambers, Jeanne C.; Pyke, David A.; Miller, Richard F.; Tausch, Robin J.; Schupp, Eugene W.; Rau, Benjamin; Gruell, TrevorPre-USGS Publications
To Burn or Not to Burn? A Framework to Answer the Question
Prescribed burns are a common tool used by land managers to control invasive plant species and to promote native plants. There are many benefits to using a prescribed burn as a management tool; however, controlling fire is often difficult as it can be unpredictable. FRESC research ecologist Dave Pyke sat down with us to speak about a new framework that he has developed for
Interpreting Indicators of Rangeland Health – Version 5
Qualitative assessments of rangeland health using observable indicators help managers make informed land management decisions and communicate findings with the public.
Post-Fire Growth of Seeded and Planted Big Sagebrush – Strategic Designs for Restoring Greater Sage-grouse Nesting Habitat
Recent wildfire-induced losses of big sagebrush are outpacing natural recovery and leading to substantial losses in habitat for species such as greater sage-grouse.
Biological Soil Crusts in Ecological Restoration: Emerging Research and Perspectives
In this introductory paper for a special issue of the journal Restoration Ecology focused on the restoration of biological soil crusts, authors summarize the importance of biological soil crusts, as well as emerging research efforts using biocrusts in ecological restoration.
Weed-Suppressive Bacteria Did Not Control Bromus tectorum
Recent trials using a bacterial bioherbicide known as D7 have had mixed results in controlling invasive annual grasses in rangelands.
Components and Predictors of Biocrusts
Although biological soil crusts occur globally in arid and semi-arid environments, the occurrence of biocrusts has not previously been related to individual plant communities at regional scales.
Passive Restoration of Vegetation and Biocrusts
Livestock exclosures established in response to the 1934 Taylor Grazing Act offer a chance to quantify reference conditions for biological soil crusts, which are largely unknown.
Two Promising Tackifiers may Enhance Moss Growth for Biocrust Restoration
Establishing mosses could be valuable in restoring biological soil crusts following disturbance, yet a good method for delivering and establishing moss propagules is lacking.
Why Sagebrush Re-establishment After Fire is so Difficult
Big sagebrush ecosystems are particularly sensitive to wildfires and life history information on big sagebrush is scarce and vital for restoration success.
Effects of Disturbance on Vascular Plants and Biocrusts in Sagebrush Steppe
Semi-arid sagebrush ecosystems experience chronic disturbances through grazing, invasive grasses, and acute disturbance of fire. Biocrusts, a community of cyanobacteria, mosses, and lichens, develop on soil surfaces and contribute to the land’s resistance to invasive plants.
Protocol for Describing Indicators of Rangeland Health
Assessing rangeland health is useful from a land management perspective in providing a baseline or early indicator of degradation and for prioritizing habitat across a landscape for restoration.
Sagebrush Steppe Resilience and the Interaction of Climate and Management
Invasive grass species are a threat to many ecosystems around the world and in sagebrush habitats of the western United States, presence of non-native grasses may give rise to fire cycles that lead to a loss of sagebrush and a dominance of invasive cheatgrass.
Understanding the Ecological Importance of Biocrusts and Grazing Prescriptions that Minimize their Disturbance
Biocrusts develop on the surface of soils, comprised of a community of cyanobacteria, mosses, and lichens, and they are commonly found across natural areas in the arid and semi-arid Western U.S.