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Our Team

The Nutrient Management Spear Program (NMSP) was initiated in August 2000 when Quirine Ketterings joined the faculty of the Department of Crop and Soil Sciences at Cornell University as assistant professor of nutrient management in agricultural systems. The NMSP and its applied research and extension mission in field crop nutrient management relocated to the Department of Animal Science in July of 2008.

  • Karl Czymmek, PRO-DAIRY's senior extension associate in nutrient management is a key collaborator in the NMSP.
  • Greg Godwin, research support specialist, joined us in August of 2002. Greg carries responsibilities for our field-based research program, with specific focus on manure application method studies for corn, alfalfa and grass.
  • Sheryl Swink, program aide, joined us as in the fall of 2002 to work on our Starter Phosphorus Project at that time, and is currently working on updating of our corn yield potential database.
  • Sanjay Gami, research associate, joined our team in December of 2008 to support and lead laboratory-based projects. He is in charge of laboratory analyses and management and worked on our project on implication of land application of acid whey.

We have several postdoctoral researchers in our team. New technologies such as yield monitor system, satellite imagery and unmanned aerial vehicles (UAVs or drones) are generating large sets of data that are valuable for making precision agriculture decisions. Two of our postdocs work on precision agriculture. A third postdoc works on evaluation of the phosphorus runoff index and whole farm nutrient mass balances, in collaboration with certified nutrient management planners and farmers:

  • Tulsi Kharel received his PhD from South Dakota State University. Originally from Nepal, his work in our team involves analyzing such datasets using advanced hierarchical statistical modeling. Tulsi's work aims to develop methodology and protocols for use and processing of datasets for agricultural decisions (yield monitor data, satellite images, crop sensor data, soil data etc.).
  • Angel Maresma graduated with a PhD from the University of Lleida in Spain, where he is originally from. After a 4 month internship with us in 2015, he returned to our team in April of 2017 to work on precision agriculture for corn and forage sorghum, with specific focus on use of drones and crop sensors for more efficient nitrogen fertilization strategies. Multispectral aerial images derived from drones services, as well as active sensor scanning, are used to determine in-season nitrogen requirements of corn and sorghum and to predict grain and forage yields.
  • Mart Ros, originally from the Netherlands, is currently finishing his PhD in Wageningen University, and joined us in May of 2017. Mart is working with several consulting firms and extension educators as well as state agencies in the Northeast on our regional phosphorus index evaluation project. In addition, he works with many farms on their whole farm nutrient mass balance as assessment tool in the adaptive management process.

We are wrapping up journal articles with three recent postdoctoral researchers:

  • Amir Sadeghpour, originally from Iran, joined us in February of 2014 and left in January of 2016 to pursue a postdoctoral position at Virginia Tech. Amir led our project on greenhouse gas emissions from manure, compost and fertilizer management, corn, alfalfa and grass systems.
  • Aristotelis Tagarakis, originally from Greece, who joined us in July 2014 to lead our crop sensor precision agriculture program and went back to Greece at the end of December of 2016.
  • Steve Crittenden, originally from Canada, graduated with a PhD from Wageningen University in the Netherlands and worked with us us in July of 2015 until August 2017 on the P Index and whole farm mass balance projects.

We currently have one graduate student in our program:

  • Sarah Lyons, Ph.D. student, joined us in August of 2015 to work on production (agronomic practices) and feeding of alternative forages including winter cereals such as cereal rye and triticale, and brown midrib forage sorghum.

We continue to wrap up journal articles on a field crops related project, including image-based assessment of biomass of cover crops with Keenan and the tradeoffs between yield and quality of double crops grown for forage with Jeff.

  • Keenan McRoberts, PhD graduate in Animal Science (advisor Dr. Debbie Cherney).
  • Jeff Liebert, MS graduate in Soil and Crop Sciences (advisor Matt Ryan).

We greatly enjoy working with undergraduates, through independent research projects, work-study programs, and internships. Currently we have three undergraduates in our program: Sarah Hetrick (Agricultural Sciences and Plant Sciences), Jordi Verhoeven (Animal Science), and Brady Rogers (Agricultural Sciences).

Lisa Fields, independent consultant, writes student and project impact stories for us. We contracted with Peter Barney, who retired from Cornell Cooperative Extension of St. Lawrence County in December of 2007, for on-farm projects in St. Lawrence County, and with Tom Kilcer, who retired from Cornell Cooperative Extension of Rensselaer County in June of 2009, for projects at the Valatie Research Farm and surrounding farms in eastern New York.

A major role in the program is played by Cornell Cooperative Extension Field Crops Educators.

Biographies/Curriculum Vitae

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