Current Research

Nitrogen Decision Support Tool

Perhaps the signature research work of the lab thus far is the development of a novel nitrogen decision support tool (N tool) for corn, which allows a user to input site-specific soil and cover crop data to calculate a fertilizer recommendation for corn that accounts for N availability from soil organic matter and cover crop residues. Recommendations can be calculated for a single field using a graphical web-based application available on the Penn State Extension Website. The theory behind how the tool works, along with the equations used in the calculations, is described in the article "Soil Organic Matter and Cover Crop-based Nitrogen Recommendations for Corn" also found on the extension website.

Improvement and validation of the Nitrogen Decision Support Tool

A series of research projects are being conducted in collaboration with the Penn State Agriculture and Environment Center (AEC), other Penn State research labs, statewide NGOs, federal and state government funding agencies, and farmers and stakeholders across Pennsylvania:

  • Improving the accuracy of N tool predictions using measurements of microbial carbon use efficiency (CUE) obtained through field- and lab-based methods such as litterbag decomposition and microbial incubations
  • Validating the accuracy of N tool predictions given a diversity of modern no-till, cover crop, and manure application practices by annually conducting a series of on-farm nitrogen response trials in corn
  • Assessing the nitrogen availability from manure to a subsequent corn crop in a no-till cropping system with a cover crop managed in different ways; thereby updating Penn State Agronomy Guide recommendations and addressing a limitation when generating accurate supplemental nitrogen fertilizer recommendations for corn under the new framework
  • Developing rapid, low-cost assessments of soil carbon and nitrogen pools used to make N tool predictions using FTIR mid-infrared spectroscopy
  • Using satellite imagery to scale-up cover crop N content measurements for extensive deployment of N tool recommendations

Thriving Agricultural Systems in Urbanized Landscapes

The Thriving Agricultural Systems project is a 5-year, $9 million project funded by USDA's National Institute of Food and Agriculture (NIFA) with an ambitious goal to help create economically thriving and environmentally beneficial agricultural systems in urbanized landscapes. These agricultural systems are located in metropolitan counties and in non-metropolitan counties adjacent to urban areas, and are vital to the sustainability of U.S. agriculture. Over 60% of U.S. net farm income comes from these urbanized landscapes.

Specifically, the Soil Fertility lab is part of a task team conducting research to enhance field-scale nutrient use efficiency (NUE) at an adaptive watershed management site.  We implement a suite of best management practices (BMPs) including cover crops, variable rate nitrogen fertilizer prescriptions, and Nitrogen Decision Support Tool recommendations within a conventional cash grain cropping system and monitor water quality changes over the life of the project.

Thriving Ag website

Validating novel fertilizer products and technologies

We routinely collaborate with private industry to conduct field trials of novel fertilizer technologies and soil amendments. Recent topics of work include:

  • Enhanced efficiency nitrogen fertilizer technologies
  • Microbial products providing biological N fixation for corn
  • The soil fertility effects of using basalt rock dust to sequester atmospheric carbon through enhanced mineral weathering processes
  • Aluminum oxide soil amendments to mitigate phosphorus deficiencies and excesses


Charles White
  • Assistant Professor and Extension Specialist, Soil Fertility and Nutrient Management


Charles White
  • Assistant Professor and Extension Specialist, Soil Fertility and Nutrient Management