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Germάn Bollero

Germάn Bolero
Dean of the College of Agricultural, Consumer and Environmental Sciences

225 Mumford Hall, MC 710 1301 W. Gregory Dr. Urbana IL 61801

Program Areas
Extension Administration and Leadership

Mission Statement

Dr. Bollero utilizes advanced statistical methods to define, quantify, and find solutions to increase productivity and profitability of food systems while reducing undesirable impacts of agricultural practices on ecosystems. His accurate modeling and interpretation of cropping system productivity and environmental services drive future agricultural and environmental practices.


  • Ph.D.: Agronomy, University of Illinois at Urbana-Champaign — 1994
  • M.S.: Agronomy, University of Illinois at Urbana-Champaign — 1993
  • B.S.: Agronomy, National University of Rosario, Argentina — 1986


Dean Dr. Germán Bollero brings more than a decade of administrative leadership to the role, having served as associate dean for research and head of the Department of Crop Sciences. More importantly, he has been a member of the ACES family for nearly 30 years.

Bollero is a native of Rosario, Argentina. After receiving a bachelor's degree in agronomy from the National University of Rosario, Argentina, he came to the University of Illinois to continue his education. He earned his master's degree and Ph.D. from the Department of Agronomy (now Crop Sciences), and continued on as a postdoctoral research associate and senior research specialist in agriculture. In 1998, he joined the Crop Sciences faculty as assistant professor of biometry and cropping systems. Bollero then led the department as head from 2009 to 2018. In 2018, he became associate dean for research and director of the Illinois Agricultural Experiment Station, investing in convergent research collaborations across the college and campus.

Bollero is internationally recognized for his scholarship in biometry and cropping systems. His teaching, service, and research contributions have placed him among an elite handful of truly outstanding faculty members. He has been included on the Incomplete List of Teachers Ranked as Excellent by Their Students dozens of times. Among other recognitions, he has received several College of ACES awards, was selected as a member of the ACES Academy of Teaching Excellence, and was in the first class of the ACES Global Connect program. Dr. Bollero is a Fellow of the Crop Science Society of America and the Agronomy Society of America.

Resident Instruction

Selected Articles in Journals

  • Farias Neto, A.F. G.L. Hartman, W.L. Pedersen, S. Li, G. Bollero, and B.W. Diers.  2006.  Irrigation and inoculation treatments that increase the severity of soybean sudden death syndrome in the field.  Crop Sci. 46: 2547-2554.
  • Martín, N.F., G.A. Bollero, N.R. Kitchen, A.N. Kravchenko, K. Sudduth, W.J. Wiebold, and D.G. Bullock. 2006. Two classification methods for developing and interpreting productivity zones using site properties. Plant Soil 288: 357-371.
  • Ruffo, M.L., G.A. Bollero, D.S. Bullock, and D.G. Bullock. 2006. Site-specific production functions for variable rate corn nitrogen fertilization. J. Precision Agric. 7:327–342.
  • Villamil, M.B., G.A. Bollero, R.G. Darmody, F.W. Simmons, and D.G. Bullock. 2006. No-till corn-soybean systems including winter cover crops: effects on soil properties. Soil. Sci Soc. Am. . J. 70:1936-1944.
  • Miguez, F.E. and G.A. Bollero. 2006. Winter cover crops in Illinois: evaluation of ecophysiological characteristics of corn. Crop Sci. 46: 1536-1545.
  • Morgan P.B., T.A. Mies, G.A. Bollero, R.L. Nelson, and S.P. Long. 2006. Season-long elevation of ozone concentration to projected 2050 levels under fully open-air conditions substantially decreases the growth and production of soybean. New phytologist 170:333-343.
  • Bierman, R.E., D.E. Riechers, C.L. Sprague, G. Bollero, and W.L. Pedersen. 2006. Fungicide-herbicide interaction in soybean (Glycine max). Crop Prot. 25: 134-139.
  • Rayburn, A.L.,R. McCloskey, T. C. Tatum, G. A. Bollero, M. R. Jeschke, and P. J. Tranel. 2005. Genome Size Analysis of Weedy Amaranthus Species. Crop Sci. 45:2557-2562.
  • Ruffo, M.L., G. A. Bollero, D.G. Bullock, and R.G. Hoeft. 2005. Spatial Variability of the Illinois Soil Nitrogen Test: Implications for Soil Sampling. Agron. J. 97:1484-1492.
  • Miguez, F.E. and G.A. Bollero. 2005. Review of corn yield response under winter cover cropping systems using meta-analytic methods. Crop Sci. 45:2318-2329.
  • Dann H. M., D. E. Morin, G.A. Bollero, M. R. Murphy, and J. K. Drackley. 2005. Prepartum intake, postpartum induction of ketosis, and periparturient disorders affect the metabolic status of dairy cows. Journal of Dairy Science 88: 3249-3264.
  • K.A. Sudduth, N.R. Kitchen, W.J. Wiebold, W.D. Batchelor, G.A. Bollero, D.G. Bullock, D.E. Clay, H.L. Palm, F.J. Pierce, R.T. Schuler, K.D. Thelen. 2005. Relating apparent electrical conductivity to soil properties across the north-central USA Computers And Electronics In Agriculture 46: 263-283.
  • Adee, E.A., Paul, L. E., Nafziger, E. D., and Bollero, G. 2005. Yield loss of corn hybrids toincremental defoliation. Online. Crop Management doi:10.1094/CM-2005-0427-01-RS.
  • Morgan, P.B., G.A. Bollero, R.L. Nelson, F.G. Dohleman and S.P. Long. 2005. Increase in above-ground net primary production and yield of soybean is less when [CO2] is elevated in the open. Global Change Biology 11:1-10.
  • Martin, N. F., G.A. Bollero and D.G. Bullock. 2005. Associations between field characteristics and soybean plant performance using canonical correlation analysis. Plant Soil 273:39-55.
  • Crandall, S.M., M.L. Ruffo, and G.A. Bollero. 2005. Cropping system and nitrogen dynamics under a cereal winter cover crop preceding corn. Plant Soil 268:209-219.
  • Ruffo, M. L., D. G. Bullock, and G. A. Bollero. 2004. Soybean yield as affected by biomass and nitrogen uptake of cereal rye in winter cover crop rotations. Agron. J. 96:800-805.
  • Yeater, K.M., G.A. Bollero, D.G. Bullock, and A.L. Rayburn. 2004. Flow cytometric analysis for ploidy level differentiation of 45 hairy vetch accessions. Anal. Appl. Biol. 145:123-127.
  • Officer, S. J., A. N. Kravchenko, G. A. Bollero, K. A. Sudduth, N. R. Kitchen, W. J. Wiebold, H. L. Palm, and D. G. Bullock. 2004. Relationships between soil bulk electrical conductivity and the principal component analysis of topography and soil fertility values. Plant Soil. 258: 269-280.
  • Yeater, K.M., G.A. Bollero, D.G. Bullock, A.L. Rayburn, and S. Rodriguez-Zas. 2004. The use of canonical discriminant analysis for selection of hairy vetch. Crop Sci. 44:185-189.
  • Young, B.G., J.M. Young, J.L. Matthews, M.D.K. Owen, I.A. Zelaya, R.G. Hartzler, L.M. Wax, K.W. Rorem, and G.A. Bollero. 2003. Soybean development and yield as affected by three postemergence herbicides. Agron. J. 95: 1152-1156.
  • Ruffo, M. L., F. O. Garcia, G. A. Bollero, K. Fabrizzi, and R. A. Ruiz. 2003. Effects of nitrogen fertilizer on sunflower in South-East Buenos Aires, Argentina. Commun. Soil Sci. Plant Anal. 34:2645-2657.
  • Yeater, K.M., G.A. Bollero, D.G. Bullock, A.L. Rayburn, and S. Rodriguez-Zas. 2003. The use of canonical discriminant analysis for selection of hairy vetch. Crop Sci. 44:185-189.
  • Steckel, L.E., C.L. Sprague, A.G. Hager, F.W. Simmons, and G.A. Bollero. 2003. Effects of shading on common waterhemp growth and development. Weed Sci. 51:898-903.
  • Hager A.G., L.M. Wax, E.W. Stoller, and G.A. Bollero. 2003. Influence of diphenylether herbicide application rate and timing on common waterhemp control in soybean. Weed Tech. 17:14-20.
  • Ruffo, M.L., and G.A. Bollero. 2003. Residue decomposition and C and N release rates prediction based on biochemical fractions using principal component regression. Agron. J. 95: 1034-1040.
  • Ruffo, M.L., and G.A. Bollero. 2003. Modeling rye and hairy vetch residue decomposition as a function of degree-days and decomposition-days. Agron. J. 95: 900-907.
  • Sudduth, K.A., N.R. Kitchen, G.A. Bollero, and D.G. Bullock. 2003. Comparison of electromagnetic induction and direct sensing of soil electrical conductivity. Agron. J. 95: 472-482..
  • Taylor-Lovell, S., L.M. Wax, and G.A. Bollero. 2002. Preemergence flumioxazin and pendimethalin and postemergence herbicide systems for soybean (Glycine max) Weed Tech. 16: 502-511.
  • Hager A.G., L.M. Wax, G.A. Bollero, and F.W. Simmons. 2002. Common waterhemp (Amaranthus rudis Sauer) management with soil-applied herbicides in soybean (Glycine max (L) Merr.). Weed Sci. 5: 607-610.
  • Hadley, C.I., K.R. Olson, G. A. Bollero, and G.E. Pepper. 2002. Predicting forage yields using properties of Illinois soils, USA. Pakistan J. Agron. 1:1-8.
  • Hager A.G., L.M. Wax, E.W. Stoller, and G.A. Bollero. 2002. Common waterhemp (Amaranthus rudis) interference in soybean. Weed Sci. 5: 607-610.
  • McGuire N.C., R. Schulman, M.D. Ridgway, and G. A. Bollero. 2002. Detection of occult urinary tract infections in dogs with diabetes mellitus. J. Amer. Anim. Hospital Assoc. 38: 541-544.
  • Kravchenko A.N., G.A. Bollero, R.A. Omonode, and D.G. Bullock. 2002. Quantitative mapping of soil drainage classes using topographical data and soil electrical conductivity. Soil. Sci. Soc. Amer. J. 60:235-243.
  • Ratcliffe S.T., H.M. Robertson, C.J. Jones, G.A. Bollero, and R.A. Weinzierl. 2002. Assessment of parasitism of house fly and stable fly pupae (Diptera: Muscidae) by pteromalid (Hymenoptera: Pteromalidae) parasitoids using polymerase chain reaction. J. Med. Entomol. 39: 52-60
  • Woolery, M.E., K.R. Olson, J. O. Dawson, and G. A. Bollero. 2002. Using soil properties to predict forest productivity in southern Illinois. J. Soil Water Conserv. 57:37-45.
  • Wander, M.M., G.L. Walter, T.M. Nissen, G.A. Bollero, S.S. Andrews, and D.C. Cavanaugh-Grant. 2002. Soil quality: Science and process. Agron. J. 94:23-32.
  • Cooperband, L.R. G.A. Bollero, and F.J. Coale. 2002. Effect of poultry litter and composts on soil nitrogen and phosphorus availability and corn production. Nutrient Cycling in Agroecosystems 62: 185-194.

Journal Editorships

  • Associate Editor, Crop Sciences, 2004-present
  • Associate Editor, Agronomy Journal, 2000-2005

Professional Societies

  • American Society of Agronomy
  • Crop Science Society of America
  • Soil Science Society of America

Professional Highlights

  • Needelman B.A., M.M. Wander, GA Bollero, C.W. Boast, G.K. Sims, and D.G. Bullock, 1998. Interaction Between Tillage Practices And Soil Texture: Biologically-Active Soil Organic Matter In Illinois. In Press Soil Science Society of America Journal.
  • Wander M.M. and GA Bollero. 1998. Soil Quality Assessment in Illinois. In Press Soil Science Society of America Journal.
  • Walter, G, M. Wander, and GA Bollero. 1997, A Farmer-Centered Approach to Developing Information for Soil Resource Management: The Illinois Soil Quality Initiative. American Journal of Alternative Agriculture 12(2): 64-72.
  • Bollero, GA, D.G. Bullock, and S.E. Hollinger. Soil Temperature and Planting Date Effects on Yield, Leaf Area, and Plant Development. Agronomy Journal vol. 88, no. 3, May-June 1996.
  • Bollero, G.A. and D.G. Bullock, Cover Cropping Systems for the Central Corn Belt, Journal of Production Agriculture, Vol. 7, no. 1, 1994.