VRA liming application using Veris EC and pH mapping

        Date    
          31-Jan-05    
             
Project Title              
  Variable rate lime application prescription from Veris EC & pH mapping.
 
             
Investigator 1       Investigator 2      
  Scheufler Farms, Inc., 1810 22nd Road, Sterling, KS  67579    
   
   
   
Phone 620-257-2508     Phone      
cell phone 620-257-8333            
Email Lee@ScheuflerFarms.com Email      
               
             
Statement of Problem            
               
Lime requirements in central Kansas are variable.  Lime is an expensive soil amendment, thus variable application holds promise as a precision ag technology that can be cost effective and environmentally friendly.  Collecting data with enough precision to meaningfully apply lime has been expensive.  With the new technology (Veris MSP for pH and EC) there is an opportunity to collect adequate data to make good prescriptions at a lower cost.
             
Project Objectives            
               
Developing a method of writing a lime prescription application using information from Veris EC and Veris pH.
             
Methodology              
               
We will collect EC and pH measurements using the Veris MSP at a shallow depth (about 3 inches).  This data will be analyzed and compared to the data collected previously on this field using a handheld pH device.  The previous data were collected before and one year after  the application of 1 ton (65% ECC) lime.  The data points were from a systematically unaligned grids of one acre.  Previous attempts at analysis were unclear.  With the collection of more intense pH data (probably 60 foot swath patterns) generating about 10 pH samples per acre, we hope to be able to develop an algorithm for future applications of lime to this field.  The field we have chosen is 3 miles east of Sterling, KS and consists of 240 acres of nearly level Farnum Slickspots complex, Carwile fine sandy loam, Farnum fine sandy loam and Tabler clay loam.  Previous work on this field by John Schmidt demonstrated the cost benefits to variably applying lime in this field.
             
Expected outcome / Benefit to KARA          
Develop a method for other producers to apply to their own fields to write variable rate prescription maps from Veris EC and pH.  The previous uniform application will allow the calculation of a site specific lime response for any additional lime requirement.