Matt Ryan

Professor, School of Integrative Plant Science, Soil and Crop Sciences Section

I am an agroecologist and conducts research on sustainable cropping systems. Over the next several decades, farmers need to adapt to increased climate variability, decrease their environmental impact, and feed billions of more people. Despite these challenges, it is an exciting time to be involved in agriculture, as more consumers want to know about the practices used to produce their food and new farmers are increasingly from non-farm backgrounds.

Interests

Sustainable cropping systems and agroecology

Cover crops and ecological weed management

Organic production

Recent Research

I conduct research on agroecology and sustainable cropping systems. I work with farmers, extension educators, researchers, and others to develop solutions to problems in agriculture.

Replacing external inputs with ecological processes and more fully utilizing biotic interactions is a central theme. I explore the use of crop rotation, cover crops, and intercropping to diversify cropping systems, regenerate soil health, enhance biodiversity, suppress weeds and other pests, and increase resilience to climate change. I also conduct research on perennial grain crop production and market development. In addition to applied agronomic field research, I am interested in digital agriculture, theoretical ecology, social ecological systems, and sustainability assessment.

Selected Publications

Google Scholar profile and publications.

N Tilhou, L Kissing Kucek, V Moore, S Hanson, C Reberg-Horton, MR Ryan, NJ Ehlke, A Bartow, B Carr, J Douglas, J Englert, J Raasch, AJ Woodard, J Crawford, R Crawford, S Ali, S Bhamidimarri, S Mirsky, MJ Monteros, G Moore, AV Gamble, N Rajan, S Narayanan, ER Haramoto, NT Basinger, VR Sykes, A McWhirt, MS Reiter, H Riday. 2025. Hairy vetch (Vicia villosa Roth) germplasm contains a cryptic second species (Vicia varia Host). Crop Science, 65, e21455
Tilhou, N, L Kissing Kucek, V Moore, S Hanson, SC Reberg-Horton, MR Ryan, N Ehlke, A Bartow, B Carr, J Douglas, J Englert, J Crawford, R Crawford, S Ali, S Bhamidimarri, SB Mirsky, MJ Monteros, R Hayes, and H Riday. 2025. Seed size has a major impact on fall seedling vigor in the cover crop hairy vetch (Vicia villosa). Crop Science 65, e21439.
Menalled, UD, N Djuric, RG Smith, DG Baas, A Basche, ER Haramoto, D Park, KA Renner, KL Tully, SE Wortman, and MR Ryan. 2024. The Cover Crop Challenge: An experiential learning activity for teaching students about cover crop mixtures. Natural Sciences Education 53, e70002.
Menalled, UD, KA Bybee-Finley, RG Smith, A DiTommaso, HM Darby, SJ Pethybridge, and MR Ryan. 2024. Legacy effects of annual and perennial crop diversity on weed-crop competition in maize. npj Sustainable Agriculture 2.
Ryan, MR, TJ Rose, S Wayman, CJ Pelzer, and UD Menalled. 2024. Rolled-crimped cover crops for organic no-till planted winter wheat (Triticum aestivum). Agrosystems, Geosciences & Environment 7, e70015.
Kucek, LK, K Muller, LB Martins, C Reberg-Horton, VM Moore, SB Mirksy, J Englert, L Drinkwater, J Douglas, SS Eagen, T Butler, MR Ryan, A Casey, K Clark, N Ehlke, J Hendrickson, J Guretzky, H Johnson, D Archer, RJ McGee, S Ali, A Bartow, V Bullard, AN Burke, R Barrett, C Bernau, B Carr, R Crawford, K Griffin, E Henriquez Inoa, H Hillhouse, M Smither-Kopperl, S Krogman, S Lee, A Marion, N McGee, I Silvernail, P Thevar, S Wayman, J Wayment, NP Wiering, D Wiggans, and H Riday. 2024. Genetic and environmental drivers of legume cover crop performance: Hairy vetch. Crop Science 64:3052-3072.
Allen, J, UD Menalled, G Adeux, CJ Pelzer, S Wayman, AB Jernigan, S Cordeau, A DiTommaso, and MR Ryan. 2024. Fertility and tillage intensity affect weed community diversity and functional structure in long-term organic systems. Ecological Applications 34(7): e3029
Boniface, HS, SB Mirsky, MR Ryan, RG Smith, VJ Ackroyd, KA Bybee-Finley, HM Darby, SW Duiker, M Hashemi, SM Hirsh, I Krezinski, EB Mallory, TR Mazzone, T Molloy, A Siller, R Thapa, MJ VanGessel, JM Wallace, ND Warren, S Wayman, and KL Tully. 2024. Environmental conditions outweigh seeding rates for cover crop mixture performance across the Northeast US. Field Crops Research 318:109564.
Stedden, C, EM Silva, MR Ryan, E Mallory, H Darby, J Dawson, A Hartman, and ME Sorrells. 2024. Organic small grain production in the Upper Midwest and Northeast: challenges and lessons learned. Agronomy Journal 116:2735-2753.
Mortensen, DA, MR Ryan, and RG Smith. 2024. Another step on the transgene-facilitated herbicide treadmill. Pest Management Science 80:4145-4149.
Basche, A, KA Renner, ER Haramoto, UD Menalled, SE Wortman, D Park, RG Smith, DG Baas, KL Tully, and MR Ryan. 2024. Designing and implementing a synchronized multi-university cover crops course. Natural Sciences Education 53, e20141.
Huddell, AM, R Thapa, GS Marcillo, LJ Abendroth, VJ Ackroyd, SD Armstrong, G Asmita, M Bagavathiannan, KS Balkcom, A Basche, S Beam, K Bradley, LP Canisares, H Darby, AS Davis, P Devkota, WA Dick, JA Evans, WJ Everman, TF De Almeida, ML Flessner, LM Fultz, S Gailans, M Hashemi, J Haymaker, MJ Helmers, N Jordan, T Kaspar, QM Ketterings, E Kladivko, A Kravchenko, EP Law, L Lazaro, RG Leon, J Liebert, J Lindquist, K Loria, JM McVane, JO Miller, MJ Mulvaney, NV Nkongolo, JK Norsworthy, B Parajuli, C Pelzer, C Peterson, H Poffenbarger, P Poudel, MS Reiter, M Ruark, MR Ryan, S Samuelson, JE Sawyer, S Seehaver, LS Shergill, YR Upadhyaya, M VanGessel, AL Waggoner, JM Wallace, S Wells, C White, B Wolters, A Woodley, R Ye, E Youngerman, BA Needelman, and SB Mirsky. 2024. U.S. cereal rye winter cover crop growth database. Scientific Data 11:200.
Liebert, J, JH Cherney, QM Ketterings, SB Mirsky, CJ Pelzer, and MR Ryan. 2023. Winter cereal species, cultivar, and harvest timing affect trade-offs between forage quality and yield. Frontiers in Sustainable Food Systems 7:96.
Liebert, J, SB Mirsky, CJ Pelzer, and MR Ryan. 2023. Optimizing organic no-till planted soybean with cover crop selection and termination timing. Agronomy Journal 115:1938–1956.
Culman, S, P Pinto, J Pugliese, T Crews, L DeHaan, JM Jungers, J Larsen, MR Ryan, M Schipanski, MR Sulc, S Wayman, MH Wiedenhoeft, DE Stoltenberg, and V Picasso Risso. 2023. Forage harvest management impacts Kernza intermediate wheatgrass productivity across North America. Agronomy Journal 115, 2424–2438.
Rowland, AV, UD Menalled, CJ Pelzer, LM Sosnoskie, A DiTommaso, and MR Ryan. 2023. High seeding rates, inter-row mowing, and electrocution for weed management in organic no-till planted soybean. Weed Science 1-42.
Chami, B, MT Niles, S Parry, SB Mirsky, VJ Ackroyd, and MR Ryan. 2023. Incentive programs promote cover crop adoption in the northeastern United States. Agricultural & Environmental Letters 8, e20114.
Menalled, UD, CJ Pelzer, A DiTommaso, and MR Ryan. 2023. Effect of multi-tactic weed management on weed suppression and yield in the establishment year of intermediate wheatgrass. Agrosystems, Geosciences & Environment 6, e20426.
Allen, J, G Adeux, CJ Pelzer, S Wayman, AB Jernigan, S Cordeau, A DiTommaso, and MR Ryan. 2023. No yield benefit from starter fertilizer in soybean no-till planted into rolled- crimped cereal rye. Agrosystems, Geosciences & Environment 6, e20434.
Menalled, UD, RG Smith, S Cordeau, A DiTommaso, SJ Pethybridge, MR Ryan. 2023. Phylogenetic relatedness can influence cover crop-based weed suppression. Scientific Reports. Scientific Reports, 13: 17323.
Bybee-Finley, KA, UD Menalled, CJ Pelzer, L Ruhl, NP Lounsbury, ND Warren, JH Cherney, HM Darby, RG Smith, MR Ryan. 2023. Quantifying the roles of intraspecific and interspecific diversification strategies in forage cropping systems. Field Crops Research 302.
Bybee-Finley, KA, MR Ryan. 2018. Advancing intercropping research and practices in industrialized agricultural landscapes. Agriculture 8(6), 80
Nunes, MR, HM van Es, R Schindelbeck, AJ Ristow, M Ryan. 2018. No-till and cropping system diversification improve soil health and crop yield. Geoderma 328, 30-43
Mirsky, SB, MR Ryan, JR Teasdale, WS Curran, CS Reberg-Horton, JT Spargo, MS Wells, CL Keene, JW Moyer. 2013. Overcoming weed management challenges in cover crop–based organic rotational no-till soybean production in the eastern United States. Weed Technology 27(1), 193-203
Mortensen, DA, JF Egan, BD Maxwell, MR Ryan, RG Smith. 2012. Navigating a critical juncture for sustainable weed management. BioScience 62(1), 75-84
Mirsky, SB, WS Curran, DM Mortenseny, MR Ryany, DL Shumway. 2011. Timing of cover-crop management effects on weed suppression in no-till planted soybean using a roller-crimper. Weed Science 59(3), 380-389

Courses Taught

PLSCI 1900: Sustainable Agriculture: Food, Farming, and the Future
PLSCI 3800: Principles and Practices in Certified Organic Agriculture

Contact Information

1113 Bradfield Hall
Ithaca, NY 14853

(607) 255-4964

mrr232 [at] cornell.edu

Graduate Fields
- Soil and Crop Sciences
More information
Education
- Doctorate
  The Pennsylvania State University
  2010
- Master of Science
  The Pennsylvania State University
  2007
- Bachelor of Science
  Kutztown University
  2001

Matt in the news

News

June 5, 2025

From trash to treasure: Recycling organic waste supports farmers, climate

“We don’t think about waste as a resource, but we should,” added Lori Leonard, professor and chair of global development in the College of Agriculture and Life Sciences. “Our landfills are filling up, and nobody wants a new landfill in their...

Cornell University Agricultural Experiment Station
PRO-DAIRY
Food Science

News

April 17, 2025

Cover Crop Challenge lets students compete and grow

How better to learn with classmates than to soil your undies together? Students in the Cover Crops in Agroecosystems (PLSCI 4125) course learn about the importance of soil nutrient cycling by, among other things, burying a new pair of cotton...

Campus Area Farms
Cornell University Agricultural Experiment Station
School of Integrative Plant Science

Matt Ryan

Contact Information

Graduate Fields

More information

Education

Matt in the news