I. Alejandra Sierra

Assistant Professor of Turfgrass Agronomy
Horticulture Program Team, Plant and Environmental Sciences Department, PeeDee Research and Education Center

Office: 2200 Pocket Rd, Florence, SC
Phone: 954-213-2382

Email: isierra@clemson.edu

Educational Background

Ph.D. Turfgrass Science
University of Florida

M.S. Horticultural Sciences
University of Florida

B.S. Agronomy
Zamorano University

Profile

I am an Assistant Professor of Turfgrass Agronomy with a 60% Extension and 40% Research appointment in the Department of Plant and Environmental Sciences at Clemson University. Based at the Pee Dee Research and Education Center, my program focuses on improving the sustainability, resilience, and performance of managed turfgrass systems through integrated agronomic management. Working closely with golf course superintendents, sports field managers, sod producers, landscape professionals, and Extension agents, I develop and evaluate science-based management strategies that address industry needs while promoting efficient use of water, nutrients, and other resources.

Research Interests

My research program takes a holistic approach to turfgrass management by addressing the underlying factors that influence turfgrass health and performance rather than focusing solely on symptoms. Research activities include evaluating emerging management technologies and products, including fertilizers, biostimulants, soil surfactants, herbicides, and precision management tools. My broader research interests focus on the interactions among nutrient management, water conservation, soil health, and cultural practices to develop practical, data-driven strategies that improve turfgrass performance, resource-use efficiency, and long-term system sustainability.

Extension and Outreach

My extension program provides research-based information and practical management recommendations to turfgrass professionals throughout South Carolina. Educational efforts include field days, county Extension agent training, webinars, industry meetings, golf course superintendent programs, sod producer meetings, Extension publications, and trade articles. Through regular engagement with stakeholders, I seek to identify emerging industry challenges and translate research findings into effective management practices for managed turfgrass systems.

Publications

Sierra Augustinus, I. A., Unruh, J. B., Kenworthy, K. E., Lindsey, A. J., & Schiavon, M. (2026). St. Augustinegrass can sustain performance under water and fertilizer restrictions in subtropical environments. Agronomy Journal, 118, e70325.https://doi.org/10.1002/agj2.70325

Ojeokun, O., Fry, J., Todd, T., Martin, C., Chandra, A., Xiang, M., Patton, A., Amgain, N., Sierra, A., Schiavon, M., Kenworthy, K., Kruse, J., Braun, R., & Kennelly, M. (2025). Thatch accumulation in zoysiagrass genotypes across the US transition zone and southern regions. HortTechnology, 35(4), 502-512. https://doi.org/10.21273/HORTTECH05649-25

Petelewicz, P., Joseph, M. M., Sierra Augustinus, I. A., Arevalo Alvarenga, A. F., McLoughlin, P. H., Gallo, S. A., MacDonald, G. E., & Schiavon, M. (2025). Combined impact of aerification, postemergence herbicides, and post-herbicide irrigation on goosegrass control in bermudagrass putting greens. Agronomy Journal, 117, e21734. https://doi.org/10.1002/agj2.21734

Sierra Augustinus, I. A., Arevalo Alvarenga, A. F., & Schiavon, M. (2024). Bermudagrass fairway responses to various combinations of a soil surfactant and nitrogen. Agronomy Journal, 116(6), 2657-2669. https://doi.org/10.1002/agj2.21662

Arevalo Alvarenga, A. F., Barbosa, M., Sierra Augustinus, I. A., Stingl, U., & Schiavon, M. (2024). Management practices alter endophytic diazotrophic communities in CitraBlue St. Augustinegrass. Crop Science, 65(1), e21372. https://doi.org/10.1002/csc2.21372

McLoughlin, P.H., Sierra Augustinus, I.A., Arevalo Alvarenga, A.F., & Schiavon, M. (2024). Risk of nutrient leaching following over-irrigation of two warm-season turfgrasses with recycled water. Crop Science, 65(1), e21341. https://doi.org/10.1002/csc2.21341

Peppers, J. M., McElroy, J. S., Orlinski, P. M., Baird, J., Petelewicz, P., Joseph, M. M., Sierra Augustinus, I. A., & Schiavon, M & Askew, S. D. (2024). Methiozolin rate and application frequency influence goosegrass (Eleusine indica) and smooth crabgrass (Digitaria ischaemum) control in turf. Weed Technology, 38, e24. https://doi.org/10.1017/wet.2024.5

Sierra Augustinus, I. A., Boeri, P. A., Arevalo Alvarenga, A. F., Unruh, J. B., & Schiavon, M. (2024). Nutrition of Florida lawns when summer fertilizer blackout period is enforced. Crop, Forage & Turfgrass Management, 10(1), e20265. https://doi.org/10.1002/cft2.20265

Sierra Augustinus, I. A., McLoughlin, P. H., Alvarenga, A. F. A., Unruh, J. B., & Schiavon, M. (2023). Evaluation of different aerification methods for ultradwarf hybrid bermudagrass putting greens. HortTechnology, 33(4), 333-341. https://doi.org/10.21273/HORTTECH05213-23

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