As a plant ecophysiologist, I strive to understand the physiological processes that structure natural ecosystems. I am particularly interested in addressing three key questions:

  1. What are the limits of plant functioning under environmental stresses associated with climate change?
  2. How do plant responses to their environment influence community-level processes?
  3. ​How can we use this information to explain ecosystem change?

I use a variety of physiological and statistical techniques to address these questions, including leaf gas exchange, sensor networks, stable isotope analyses, plant hydraulic measurements, and bayesian modeling. Although my research has primarily focused on grasslands and savannas, I am interested in addressing similar questions in other systems as well.

For more information, check out my lab website here!

Year Started


Kansas State University, PhD Biology (2016)

Saint Joseph’s University, MS Biology (2012)

The College of New Jersey, BS Biology (2010)

External Grants

Active Grants

NSF Integrative Research in Biology: Collaborative Proposal: Integrating trait diversity across hierarchical scales to predict biological resilience in an era of extreme environmental change. Total award of $1,402,568 to two collaborators: $524,421 to University of North Carolina at Greensboro; and $878,147 awarded to University of Wyoming with subaward to SEU; Subrecipient PI: Kimberly O’Keefe, Biological Sciences. Subaward amount $341,093; grant period 2021-2026

DUE, Robert Noyce Teacher Scholarship Program: Maker Education and Community Building as Tools to Recruit, Develop, and Retain STEM Teachers. PI: Steven Fletcher; Co-PIs: Kimberly O’Keefe, Catherine Campbell, and Casey Sherman. Award amount $1,181,608; grant period 2020-2025.

Publications & Articles


*indicates undergraduate student author

O’Keefe K, Smith DD, McCulloh KA (2023) Linking stem rehydration kinetics to hydraulic traits using a novel method and mechanistic model. Annals of Botany.

McCulloh KA, Augustine SP, Goke A, Jordan R, Krieg CP, O’Keefe K, Smith DD (2022) At least it is a dry cold: the global distribution of freeze–thaw and drought stress and the traits that may impart poly-tolerance in conifers. Tree Physiology.

Rastetter EB, Kwiatkowski BL, Kicklighter DW, Barker Plotkin A, Genet H, Nippert JB, O'Keefe K, Perakis SS, Porder S, Roley SS, Ruess RW, Thompson JR, Wieder WR, Wilcox K, Yanai RD (2022) N and P constrain C in ecosystems under climate change: Role of nutrient redistribution, accumulation, and stoichiometry. Ecological Applications. e2684. doi:10.1002/eap.2684

Keen RM, Nippert JB, Sullivan PL, Ratajczak Z, Ritchey B, O’Keefe K, Dodds WK (2022) Impacts of Riparian and Non-riparian Woody Encroachment on Tallgrass Prairie Ecohydrology. Ecosystems.

O’Keefe K, Bachle S, Keen R, Tooley EG, Nippert JB (2021) Root traits reveal safety and efficiency differences in grasses and shrubs exposed to different fire regimes. Functional Ecology.

Wedel ER, O’Keefe K, Nippert JB, Hoch B*, O’Connor RC (2021) Spatio-temporal differences in leaf physiology are associated with fire, not drought, in a clonally integrated shrub. AoB PLANTS.

Berry CZ, Ávila-Lovera E, De Guzman ME, O’Keefe K, Emery NC (2021) Beneath the Bark: Assessing Woody Stem Water and Carbon Fluxes and Its Prevalence Across Climates and the Woody Plant Phylogeny. Frontiers in Forests and Global Change. DOI=10.3389/ffgc.2021.675299

O’Keefe K, McCulloh KA (2020) Do invasive jumping worms impact sugar maple (Acer saccharum) functioning during a novel invasion of a temperate forest? Biological Invasions. DOI: 10.1007/s10530-020-02360-z

O’Keefe K, Bell DM, McCulloh KA, Nippert JB (2020) Bridging the flux gap: sap flow measurements reveal species-specific patterns of water-use in a tallgrass prairie. JGR Biogeosciences. DOI: 10.1029/2019JG005446

Hart J*, O’Keefe K, Augustine S, McCulloh KA (2020) Physiological responses of germinant Pinus palustris and P. taeda seedlings to water stress and the significance of the grass-stage. Forest Ecology and Management. DOI: 10.1016/j.foreco.2019.117647

O’Keefe K, Nippert JB, McCulloh KA (2019) Plant water uptake along a diversity gradient provides evidence for complementarity in hydrological niches. Oikos. DOI: 10.1111/oik.06529

O’Keefe K, Nippert JB (2018) Drivers of nocturnal water flux in a tallgrass prairie. Functional Ecology. DOI: 10.1111/1365-2435.13072

O’Keefe K, Nippert JB (2017b) An assessment of diurnal water uptake in a mesic prairie: evidence for hydraulic lift? Oecologia DOI: 10.1007/s00442-017-3827-2

O’Keefe K, Nippert JB (2017a) Grazing by bison is a stronger driver of plant ecohydrology in tallgrass prairie than fire history. Plant and Soil DOI: 10.1007/s11104-016-3048-1

Muench AT*, O’Keefe K, Nippert JB (2016) Comparative ecohydrology between Cornus drummondii and Solidago canadensis in upland tallgrass prairie. Plant Ecology. DOI: 10.1007/s11258-016-0567-z

O’Keefe K, Swemmer A, Nippert JB (2016) Savanna tree seedlings are physiologically tolerant to nighttime freeze events. Frontiers in Plant Science 7:46. DOI: 10.3389/fpls.2016.00046

O’Keefe K, Springer CJ, Grennell J, Davis S (2014) Biofuel Development from Cellulosic Sources. in: The Plant Sciences – Ecology & the Environment, ed: Russel Monson, Springer Reference Series, Springer-Verlag Berlin Heidelberg. 2013-12-01 19:08:16 UTC

O’Keefe K, Del Cid C, Arango CP, Puetz W*, Springer CJ (2013) Elevated [CO2] does not ameliorate the negative consequences of infection with the xylem-limited bacteria Xylella fastidiosa in Quercus rubra seedlings. Castanea 78(3):216-226. DOI: 10.2179/12-040

O’Keefe K, Tomeo N, Nippert JB, Springer CJ (2013) Population origin and genome size do not impact Panicum virgatum (switchgrass) responses to variable precipitation. Ecosphere 4(3):37. DOI: 10.1890/ES12-00339.1

Department Group

School Group

School of Natural Sciences