Title: Advances in VR Nutrients
Date: Wed Jul 26, 2017
Time: 8:00 AM - 10:00 AM
Moderator: Jenni Fridgen
Variable Rate Phosphorus - What do we really know?

Much of the phosphorus (P) fertilizer applied across the US is applied using a variable rate (VR) strategy. Often we interpolate soil P data and use standard soil test interpretations to develop VR prescriptions. We need to critically examine this approach. Can traditional soil test critical values (the soil P concentration below which we expect P fertilizer response) and fertilizer recommendation systems be used under a VR management strategy? How precise are interpolated soil test maps? These questions and others will be examined as we discuss ongoing research into VR-P.

Joshua McGrath (speaker)
Extension Associate Professor
University of Kentucky
Plant Science Building
Lexington, KY 40546-0312
Extension Specialist - Agricultural Soil Management. Applied research and extension in agronomic soil fertility and nutrient management to maximize profitability, efficiency, and protect natural resources. Specializing in site-specific nutrient management, manure management, and water quality protection. Dr. Josh McGrath joined the University of Kentucky as an Associate Professor and Soil Management Specialist in July of 2014 after eight years on faculty at University of Maryland. Dr. McGrath
Length (approx): 40 min
Seasonal Variation in Soil Test Potassium: When do you sample?

Potassium, as a non-mobile nutrient, is commonly thought to stay put in soils; however, this should not imply that soil test K levels are constant throughout the year. Seasonal variability in soil test K from spring to fall (often higher in spring and lower in fall) creates issues for soil sampling and interpreting soil test results for fertilizer applications. This session will cover soil K dynamics and approaches to mitigate seasonal K variability to improve nutrient management decisions.

John Breker (speaker)
Soil Scientist
AGVISE Laboratories
604 Hwy 15 West
Northwood, ND 58267
John Breker is a soil scientist with AGVISE Laboratories. He provides information on soil fertility and plant nutrition to agronomists and growers in the Midwest, Northern Plains, and Canadian Prairies. John was raised on his family’s grain farm in southeastern North Dakota and has studied soils as an amateur or professional since 2007. He received B.S. and M.S. degrees in soil science from North Dakota State University in 2015 and 2017, respectively. With his M.S. advisor Dr. David Franzen, John studied several soil potassium testing methods, corn yield response to potassium fertilization, and the effect of sampling time on soil potassium levels.
Length (approx): 40 min
Evaluating Fertility Rates Using Spatial Analytics

Leveraging spatial analytics to calibrate fertilizer recommendations improves the efficiency of applied fertilizers. In many cases, fertilizer recommendations have not been recently updated, in part due to a lack of funding and man-power. Today's technology and the analytical capabilities allow for the optimization of field specific fertilizer recommendations that fit grower management styles and soils.

Chad Godsey (speaker)
Godsey Precision Ag, LLC
36500 Co.Rd T.5
Eckley, CO 80727
Chad Godsey was born and raised on a farm and ranch near Wray in northeastern Colorado. After graduation with a PhD in 2005 he went to work at Oklahoma State University as a Cropping System Specialist in the Department of Plant and Soil Sciences. He served as the State Specialist for most of the oilseeds produced in the state. Most of his research and extension efforts were focused on increasing the efficiency of crop production through use of technology, no-tillage, and crop rotation. During his 7 years with OSU he begin to notice a disconnect between the precision ag industry and past research that had been conducted at Universities around the US. Nobody was offering services centered on the researched and proven technologies from the Universities. If services were being offered they often times were not being used correctly. At this point Godsey Precision Ag was created in an effort to help producers better utilize precision ag. technologies to increase their profitability. Dr. Godsey is passionate about using precision ag. technologies to increase the efficiency of crop inputs.
Ben Gist (speaker)
Key Account Manager
XS Inc. / AgVeritas
1500 Perimeter Park Drive, Suite 300
Research Triangle Park, NC 27560
In his role as Key Account Manager, Ben Gist leads innovative precision ag initiatives at XSInc, a North Carolina-based software company that specializes in data collection, cleaning, integration, analysis and reporting for the agriculture and turf and ornamental industries. Ben combines his software expertise with his passion for practical applications of precision agriculture. He is also the host of the Precision Ag Insight webcast series, which features the AgVeritas precision yield analysis software from XSInc. Prior to joining the company, Ben’s background includes roles in the GIS (Geographical Information System) applications and fisheries management fields. He holds a BA from the University of North Carolina at Chapel Hill.
Length (approx): 40 min