David A Pyke
I am a scientist emeritus at the Forest and Rangeland Ecosystem Science Center. My research interests include population ecology of native and invasive plants in the Intermountain West, monitoring protocols for ecosystem integrity on wild lands, and restoration ecology of native plants on disturbed and invaded lands.
I am involved with a few of my former projects. I am completing the ten-year analysis of the SageSTEP sagebrush – cheatgrass sites. I plan to assist and continue to provide guidance to new scientists who are now leading this long-term project. I am providing guidance and insights for two other on-going projects - The Field of Sagebrush Dreams project and the Mojave grazing removal project. Field of Dreams is an attempt to transplant sagebrush and create patches of sagebrush that will be used by Greater Sage-grouse for nesting within 5 years of a fire removing sagebrush from former nesting sites. The Mojave project is examining vegetation changes after livestock grazing was removed from locations on the Mojave National Preserve 20 years ago. Amongst these interests, my wife and I plan to travel in our teardrop trailer and see other landscapes in the US and Canada and to travel internationally to enjoy new cultures. In addition, we plan to make regular visits to our home in Honolulu.
Professional Experience
1996 – 2021: Supervisory Research Ecologist, U.S. Geological Survey, Forest & Rangeland Ecosystem Science Center, Corvallis, OR
1996 – 1999: Assistant Center Director, U.S. Geological Survey, Forest & Rangeland Ecosystem Science Center, Corvallis, OR
1993 – 1996: Research Rangeland Ecologist, National Biological Survey/Service, Forest & Rangeland Ecosystem Science Center, Corvallis, OR
1992 – 1993: Research Rangeland Ecologist, Bureau of Land Management, Pacific Forest & Basin Rangeland Systems Cooperative Research & Technology Unit, Corvallis, OR
1987 – 1992: Assistant Professor, Department of Range Science, Utah State University, Logan, UT
Education and Certifications
Ph.D., Botany, Washington State University, Pullman, WA (1983)
M.S., Forest and Range Management, Washington State University, Pullman, WA (1977)
B.S., Range Management (Wildlife option), Washington State University, Pullman, WA (1976)
Affiliations and Memberships*
Ecological Society of America
British Ecological Society
Society for Ecological Restoration
Society for Range Management
Science and Products
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Outplanting Wyoming big sagebrush following wldfire: stock performance and economics
A review of fire effects on vegetation and soils in the Great Basin region: response and ecological site characteristics
Resilience to stress and disturbance, and resistance to Bromus tectorum L. invasion in cold desert shrublands of western North America
Predicting invasion in grassland ecosystems: Is exotic dominance the real embarrassment of richness?
Monitoring of livestock grazing effects on Bureau of Land Management land
Conditions favouring Bromus tectorum dominance of endangered sagebrush steppe ecosystems
Monitoring restoration impacts to endemic plant communities in soil inclusions of arid environments
Does seeding after wildfires in rangelands reduce erosion or invasive species?
Wildfire and invasive species in the west: challenges that hinder current and future management and protection of the sagebrush-steppe ecosystem: a Gap Report
Burial increases seed longevity of two Artemisia tridentata (Asteraceae) subspecies
Nitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities
A holistic strategy for adaptive land management
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
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Filter Total Items: 112Outplanting Wyoming big sagebrush following wldfire: stock performance and economics
Finding ecologically and economically effective ways to establish matrix species is often critical for restoration success. Wyoming big sagebrush (Artemisia tridentata subsp. wyomingensis) historically dominated large areas of western North America, but has been extirpated from many areas by large wildfires; its re-establishment in these areas often requires active management. We evaluated the perAuthorsEva Dettweiler-Robinson, Jonathan D. Bakker, James R. Evans, Heidi Newsome, G. Matt Davies, Troy A. Wirth, David A. Pyke, Richard T. Easterly, Debra Salstrom, Peter W. DunwiddleA review of fire effects on vegetation and soils in the Great Basin region: response and ecological site characteristics
This review synthesizes the state of knowledge on fire effects on vegetation and soils in semi-arid ecosystems in the Great Basin Region, including the central and northern Great Basin and Range, Columbia River Basin, and the Snake River Plain. We summarize available literature related to: (1) the effects of environmental gradients, ecological site, and vegetation characteristics on resilienAuthorsRichard F. Miller, Jeanne C. Chambers, David A. Pyke, Fred B. Pierson, C. Jason WilliamsResilience to stress and disturbance, and resistance to Bromus tectorum L. invasion in cold desert shrublands of western North America
Alien grass invasions in arid and semi-arid ecosystems are resulting in grass–fire cycles and ecosystem-level transformations that severely diminish ecosystem services. Our capacity to address the rapid and complex changes occurring in these ecosystems can be enhanced by developing an understanding of the environmental factors and ecosystem attributes that determine resilience of native ecosystemsAuthorsJeanne C. Chambers, Bethany A. Bradley, Cynthia S. Brown, Carla D'Antonio, Matthew J. Germino, James B. Grace, Stuart P. Hardegree, Richard F. Miller, David A. PykePredicting invasion in grassland ecosystems: Is exotic dominance the real embarrassment of richness?
Invasions have increased the size of regional species pools, but are typically assumed to reduce native diversity. However, global-scale tests of this assumption have been elusive because of the focus on exotic species richness, rather than relative abundance. This is problematic because low invader richness can indicate invasion resistance by the native community or, alternatively, dominance by aAuthorsEric Seabloom, Elizabeth Borer, Yvonne Buckley, Elsa E. Cleland, Kendi Davies, Jennifer Firn, W. Stanley Harpole, Yann Hautier, Eric M. Lind, Andrew MacDougall, John L. Orrock, Suzanne M. Prober, Peter Adler, Juan Alberti, T. Michael Anderson, Jonathan D. Bakker, Lori A. Biederman, Dana Blumenthal, Cynthia S. Brown, Lars A. Brudvig, Maria Caldeira, Cheng-Jin Chu, Michael J. Crawley, Pedro Daleo, Ellen Ingman Damschen, Carla M. D'Antonio, Nicole M. DeCrappeo, Chris R. Dickman, Guozhen Du, Philip A. Fay, Paul Frater, Daniel S. Gruner, Nicole Hagenah, Andrew Hector, Aveliina Helm, Helmut Hillebrand, Kirsten S. Hofmockel, Hope C. Humphries, Oscar Iribarne, Virginia L. Jin, Adam Kay, Kevin P. Kirkman, Julia A. Klein, Johannes M.H. Knops, Kimberly J. La Pierre, Laura M. Ladwig, G. John, Andrew D.B. Leakey, Qi Li, Wei Li, Rebecca McCulley, Brett Melbourne, E. Charles, Joslin L. Moore, John Morgan, Brent Mortensen, Lydia R. O'Halloran, Meelis Pärtel, Jesús Pascual, David A. Pyke, Anita C. Risch, Roberto Salguero-Gómez, Mahesh Sankaran, Martin Schuetz, Anna Simonsen, Melinda Smith, Carly Stevens, Lauren Sullivan, Glenda M. Wardle, Elizabeth M. Wolkovich, Peter D. Wragg, Justin Wright, Louie YangMonitoring of livestock grazing effects on Bureau of Land Management land
Public land management agencies, such as the Bureau of Land Management (BLM), are charged with managing rangelands throughout the western United States for multiple uses, such as livestock grazing and conservation of sensitive species and their habitats. Monitoring of condition and trends of these rangelands, particularly with respect to effects of livestock grazing, provides critical informationAuthorsKari E. Veblen, David A. Pyke, Cameron L. Aldridge, Michael L. Casazza, Timothy J. Assal, Melissa A. FarinhaConditions favouring Bromus tectorum dominance of endangered sagebrush steppe ecosystems
1. Ecosystem invasibility is determined by combinations of environmental variables, invader attributes, disturbance regimes, competitive abilities of resident species and evolutionary history between residents and disturbance regimes. Understanding the relative importance of each factor is critical to limiting future invasions and restoring ecosystems. 2. We investigated factors potentially controAuthorsMichael D. Reisner, James B. Grace, David A. Pyke, Paul S. DoescherMonitoring restoration impacts to endemic plant communities in soil inclusions of arid environments
Soil inclusions are small patches of soil with different properties than the surrounding, dominant soil. In arid areas of western North America, soil inclusions called slickspot soils are saltier than adjacent soil and support different types of native vegetation. Traditional sagebrush restoration efforts, such as using drills to plant seeds or herbicides to control invasive vegetation, may damageAuthorsMounir Louhaichi, David A. Pyke, Scott E. Shaff, Douglas E. JohnsonDoes seeding after wildfires in rangelands reduce erosion or invasive species?
Mitigation of ecological damage caused by rangeland wildfires has historically been an issue restricted to the western United States. It has focused on conservation of ecosystem function through reducing soil erosion and spread of invasive plants. Effectiveness of mitigation treatments has been debated recently. We reviewed recent literature to conduct a meta-analysis of seeding after wildfires toAuthorsDavid A. Pyke, Troy A. Wirth, Jan L. BeyersWildfire and invasive species in the west: challenges that hinder current and future management and protection of the sagebrush-steppe ecosystem: a Gap Report
The Western Association of Fish and Wildlife Agencies (WAFWA) to satisfy the 45-day report requirement identified in Cooperative Agreement (F13AC00353) between WAFWA and the U. S. Fish and Wildlife Service (FWS) submit this “Gap Report”. This report summarizes the policy, fiscal and science challenges that land managers encounter related to the control and reduction of the invasive plant/fire compAuthorsKenneth F. Mayer, Pete Anderson, Jeanne Chambers, Chad Boyd, Tom Christiansen, Dawn Davis, Shawn Espinosa, Doug Havlina, Michael Ielmini, Don Kemner, Laurie Kurth, Jeremy Maestas, Brian Mealor, Ted Milesneck, Lara Niell, Mike Pellant, David A. Pyke, Joe Tague, Jason VernonBurial increases seed longevity of two Artemisia tridentata (Asteraceae) subspecies
Premise of the study: Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an activeAuthorsUpekala C. Wijayratne, David A. PykeNitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities
Annual grass invasion into shrub-dominated ecosystems is associated with changes in nutrient cycling that may alter nitrogen (N) limitation and retention. Carbon (C) applications that reduce plant-available N have been suggested to give native perennial vegetation a competitive advantage over exotic annual grasses, but plant community and N retention responses to C addition remain poorly understooAuthorsDana L. Witwicki, Paul S. Doescher, David A. Pyke, Nicole M. DeCrappeo, Steven S. PerakisA holistic strategy for adaptive land management
Adaptive management is widely applied to natural resources management (Holling 1973; Walters and Holling 1990). Adaptive management can be generally defined as an iterative decision-making process that incorporates formulation of management objectives, actions designed to address these objectives, monitoring of results, and repeated adaptation of management until desired results are achieved (BrowAuthorsJeffrey E. Herrick, Michael C. Duniway, David A. Pyke, Brandon T. Bestelmeyer, Skye A. Wills, Joel R. Brown, Jason W. Karl, Kris M. HavstadNon-USGS Publications**
Francis, M.G., Pyke, D.A., 1996, Crested wheatgrass-cheatgrass seedling competition in a mixed-density design: Journal of Range Management, v. 49, no. 5, p. 432-438.Tanaka, J.A., Pyke, D.A., 1996, Introduction to the Sustaining Rangeland Ecosystems Symposium In Edge, W.D., Olson-Edge, S.L., eds., Proceedings of the Sustaining Rangeland Ecosystems Symposium: Special Report 953, Corvallis, OR, Oregon State University, Agricultural Experiment Station, p. 1-2.Huber-Sannwald, E., Pyke, D.A., Caldwell, M.M., 1996, Morphological plasticity following species-specific recognition and competition in two perennial grasses: American Journal of Botany, v. 83, no. 7, p. 919-931.Pyke, D.A., 1995, Population diversity with special reference to rangeland plants In West, N.E., ed., Biodiversity of Rangelands: Logan, Utah, College of Natural Resources, Utah State University, p. 21-32.Pyke, D.A., Novak, S.J., 1994, Cheatgrass demography-establishment attributes, recruitment, ecotypes, and genetic variability: U.S. Department of Agriculture, Forest Service, Intermountain Research Station General Technical Report INT-GTR-313, p. 12-21.Pyke, D.A., 1994, Ecological significance of seed banks with special reference to alien annuals: U.S. Department of Agriculture, Forest Service, General Technical Report INT-GTR-313, p. 197-201.Borman, M.M., Pyke, D.A., 1994, Successional theory and the desired plant community approach: Rangelands, v. 16, no. 2, p. 82-84.Pyke, D.A., Borman, M.M., 1993, Problem analysis for the Vegetation Diversity Project - A research and demonstration program to restore and maintain native plant diversity on deteriorated rangelands of the Great Basin and Columbia Plateau: US, Bureau of Land Management, Oregon State Office Technical Note OR-936-01, p. 100.Pyke, D.A., Thompson, J.N., 1986, Statistical analysis of survival, and removal rate experiments: Ecology, no. 67, p. 240-245.**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
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*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government