Patterns of variation in root lifespan in tree species

PhD in Ecology and Biogeochemistry (2012)

Co-advised by David Eissenstat and Erica Smithwick

Present address: Institute of Geographic Sciences and Natural Resource Research, Chinese Academy of Sciences.

This research was supported by the DOE Global Change Education Program, Graduate Research Environmental Fellowship and the National Science Foundation.

In ecology we seek to understand how multiple factors interact to impact a system. Continuing in this tradition I am interested in how many drivers, natural and human-induced, impact and potentially change terrestrial ecosystems. While my work demonstrates a particular interest below ground, my overarching goal is to provide insight into below ground processes and how they connect with and act as part of a larger whole. These efforts enable me to examine my study systems from multiple spatial and temporal perspectives ranging from a single tree root in an instant to whole landscapes over centuries.


Awards &Fellowships

Graduate Research Environmental Fellowship, Department of Energy. 2010-2013.

Andersen Travel Award. The Pennsylvania State University. 2011.

Brian Horton Award, Exemplary Service and Commitment to the Ecology Program, The Pennsylvania State University. 2010.

University Fellowship, The Pennsylvania State University. 2007-2008.

The Herbert J. Bailey Endowed Graduate Fellowship, The Pennsylvania State University. 2007-2008.

Graham Endowed Fellowship, The Pennsylvania State University. 2007-2009.

Dean's List, College of Charleston. 2005.

Student Undergraduate Laboratory Internship, National Renewable Energy Laboratory, Department of Energy. Summer 2004.


McCormack ML, Gaines KP, Pastore M, Eissenstat DM. (in press). Early season root production in relation to leaf production among six diverse tree species. Plant and Soil

McCormack ML, Crisfield E, Raczka B, Schnekenburger F, Eissenstat DM, Smithwick EAH. 2015. Sensitivity of four ecological models to adjustments in fine root turnover rate. Ecological Modelling 297:107-117

McCormack ML, Adams TS, Smithwick EAH, Eissenstat DM. 2014. Variability in root production, phenology and turnover rate among 12 temperate tree species. Ecology 95: 2224-2235

Adams TS, McCormack ML, Eissenstat DM. 2013. Foraging strategies in trees of different root morphology: the role of root lifespan. Tree Physiology 33: 940-948.<

McCormack ML, TS Adams, EAH Smithwick, DM Eissenstat. Predicting fine root lifespan from plant functional traits in temperate trees. New Phytologist, 195: 823-31 (2012).

McCormack ML, DM Eissenstat, A Prasad, EAH Smithwick. 2013. Regional scale patterns of fine root lifespan and turnover under current and future climate. Global Change Biology19:1697-1708.

Eissenstat DM, ML McCormack, Q Du. Global Change and Root Lifespan. In: A Eshel, T Beeckman (eds.). Plant roots: The Hidden Half. 4th Edition. In press.

Polverigiani S, ML McCormack, CW Mueller, DM Eissenstat. Growth and physiology of olive pioneer and fibrous roots exposed to soil moisture deficits. Tree Physiology, 32: 1228-1237 (2011).

McCormack ML and CW Fernandez. Meetings: Measuring and modeling roots, the rhizosphere, and microbial processes belowground. New Phytologist, 192: 573-575 (2011).

Drake JE, EH Delucia, A Gallet-Budynek, KS Hofmockel, ES Bernhardt, SA Billings, RB Jackson, J Lichter, ML McCormack, DJP Moore, R Oren, S Palmroth, RP Phillips, JS Pippen, SG Pritchard, KK Treseder, and AC Finzi. Nitrogen limitation of net primary production prevents soil carbon sequestration under elevated concentrations of atmospheric CO2. Ecology Letters, 14: 349-357 (2011).

McCormack ML, SG Pritchard, S Breland, MA Davis, SA Prior, GB Runion, RJ Mitchell, and HH Rogers. Soil Fungi respond more strongly than fine roots to elevated CO2 in a model regenerating longleaf pine-wiregrass ecosystem.Ecosystems, 13: 901-916 (2010).

Pritchard SG, AE Strand, ML McCormack, MA Davis, and R Oren. Mycorrhizal and rhizomorph dynamics in a loblolly pine forest during five years of free-air-CO2-enrichment (FACE). Global Change Biology, 14: 1252-1265 (2008).

Pritchard SG, AE Strand, ML McCormack, MA Davis, AC Finzi, RB Jackson, R Matamala, HH Rogers, and R Oren. Fine root dynamics in a loblolly pine forest are influenced by free-air-CO2-enrichment: a six-year-minirhizotron study. Global Change Biology, 14: 1-15 (2008).

Strand AE, SG Pritchard, ML McCormack, MA Davis, and R Oren. Irreconcilable differences: fine root lifespans and soil carbon persistence. Science, 319: 456-458 (2008).


Jones Center - Roots Roots