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Department of Agronomy, Horticulture and Plant Science

Jason Clark

Professional headshot

Title

Assistant Professor & SDSU Extension Soil Fertility Specialist

Office Building

Raven Precision Agriculture Center

Office

113

Mailing Address

Raven Precision Ag Building 113
Agronomy, Horticulture & Plant Science-Box 2100A
University Station
Brookings, SD 57007
Late-season nitrogen fertilizer application using Y-drops

Early and Late In-season Nitrogen Applications

We are evaluating the influence of early and late in-season nitrogen applications on corn growth, nitrogen uptake, and grain yield using Y-drop technology to place the nitrogen fertilizer near the corn plant.

Nitrogen deficiency symptoms in corn

Nitrogen Rate Influences Corn Health

In current research projects we are working on updating nitrogen fertilizer rate guidelines by evaluating corn's response to increasing nitrogen fertilizer rates throughout the state of South Dakota when nitrogen fertilizer is applied before planting and/or during the growing season.

Education

Ph.D. in Soil Nutrient Management | University of Minnesota-Twin Cities
2018, St. Paul, Minnesota
- Improving nitrogen fertilizer rate guidelines for corn using a mineralizable nitrogen estimate.
- Effectiveness of single and split nitrogen fertilizer applications on corn production in the Midwestern U.S.

M.S. in Plant Science | Utah State University
2014, Logan, Utah
- Tillage, herbicide timing, and nitrogen fertilizer rate effects on alfalfa stand termination and corn production.

B.S. in Agronomy | Utah State University
2011, Logan, Utah

Academic Interests

Soil Nutrient Management
Crop Nutrition

Extension Responsibilities

Soil fertility guidelines for South Dakota cropping systems

Professional Memberships

Agronomy Society of America (ASA)
Soil Science Society of America (SSSA)
Crop Science Society of America (CSSA)

Area(s) of Research

My research and extension education program is focused on determining nutrient management methods that can maintain and increase crop production while conserving and reducing inputs (water, fertilizers, chemicals, etc.) in a way that minimizes environmental impact and is profitable for farmers.

Specific research areas include:
• Determining the optimal rate and timing of fertilizer application (i.e. N, P, K, and S) for profitable crop production and optimal water quality.
• Effect of source and placement of fertilizers (N, P, and K) on crop production and air and water quality.
• Influence of cropping systems that promote soil health on adjustments needed for fertilizer rate, time, source, and placement.
• Development and use of precision agriculture technologies in crop production.

Department(s)

Links

Research Gate ProfileGoogle Scholar ProfileTwitter: SDSU Extension Agronomy @SDSUExtCropsFacebook: SDSU Extension Agronomy @SDSUExtAgronomySDState Soil Fertility YouTube ChannelInstagram: SDSU Extension Agronomy @sdsuextcropsRecommended Soil Sampling Methods for South DakotaSouth Dakota Fertilizer Recommendation GuideManaging Soil and Soil Fertility After FloodingPrevent Plant: Its Effect on Fall and Spring Fertilizing PlansFallow Syndrome: What is it and how do I deal with it?Extension Website

Open Prairie

Open PRAIRIE - Public Research Access Institutional Repository and Information Exchange

Publications