Nebraska Extension Water and Cropping System team and the Nebraska Soybean Board, and the team led by Assistant Professor Nicolas Cafaro La Menza and Professor Patricio Grassini at the UNL Department of Agronomy and Horticulture are seeking farmers to participate in a study that will evaluate the impact of potassium (K) fertilization on crop yield.

This study will look at three treatments: the “baseline” without K application plus two K application rates. The goal is to identify environments where yield is constrained by K and help to refine the current K recommendations in Nebraska.

Fields of Interest

• Sandy soils and/or low soil K levels (<200 ppm).
• Preferably, irrigated fields, but rainfed fields may also be eligible.
• Fields following corn/soybean rotation without history of manure application in previous three years.
• Fields with history of silage corn, alfalfa or straw removal are desirable (but no problem if it is not the case).

What We Need from You

• Share yield maps and/or soil tests from previous years (if available).
• Grant us access to the field(s) selected.
• Plant these fields as you usually do but, if already applying K, leave a small portion of your field (100 feet wide x 200 feet long) without K fertilizer application.
• Share management information of the field (variety, planting date, etc.).
• Once we flag the K fertilization plots, avoid wheel tracks within the flagged area, but make sure the flagged area is sprayed as the rest of the field.

What We Will Do for You

• After you plant the whole field, we will do everything: flag the area, collect soil and plant samples, apply the potassium fertilizer treatments and hand-harvest the flagged areas before you harvest the whole field.
• We will provide you a detailed analysis and report of the data from your farm.
• We will provide you soil test and grain/seed quality results from the samples taken from your field.
• We will publish the results through the On-Farm Research Network if you agree with that.

If you are interested to participate, please reach out UNL Assistant Professor Dr. Nicolas Cafaro La Menza, (308) 696-6712 or your local extension educator.