Magruder Check Sample Reports


2014 -02
2014 -04

Previous Check Sample Reports

Click on the Sample Grade to Download the Sample Report in Adobe PDF format.
Click on the Sample Number to Download the MSDS in Adobe PDF format.

FREE Membership to the Magruder Check Sample Program

November 2014 Newsletter
April 2014 Newsletter
October 2013 Newsletter
June 2013 Newsletter
Sept 2012 Newsletter

  • Request a Reserve Check Sample, A Certified Homogeneous Sample is Available - 2009-11
  • Magruder Sample Schedule and Committee Minutes
  • Magruder Payment Invoice in Adobe Format

  • Magruder Payment Invoice in Word Format

  • Magruder By-Laws
  • Magruder Brochure in Adobe Format

  • Magruder Brochure in Word Format

  • Magruder Report Form in Excel Format

  • Magruder Report Form in Adobe Format

  • Magruder Report Form in Fillable Adobe Format

  • Magruder General Instructions in Adobe Format

  • Magruder Method Codes in Word Format

  • Magruder Method Codes in Adobe PDF Format

  • Magruder Membership Application in Word Format

  • Magruder Membership Application in Adobe PDF Format

  • Instructions for Supplying Product to Magruder

  • Magruder Check Sample Statistics

  • Magruder Committee Roster

  • SUIP 25 Heavy Metals Calculator

  • Download the Adobe Acrobat PDF Reader (FREE!)


    Round robin samples are frequently used to provide comparisons of analytical results. The first such program to make use of
    comprehensive statistical techniques is the Magruder Fertilizer Check Sample Program. The program bears the name of its originator,
    Dr. E. W. Magruder. Dr. Magruder was a chemist with the F.S. Royster Guano Company. He distributed the first sample to 29 laboratories
    in November, 1922. The Royster Guano Company and its successors continued to totally support this program for 36 years, first under
    the direction of Dr. Magruder and later under the direction of Dr. S. F. Thornton.

    In 1958 the sponsorship of the program transferred from Royster to the joint co-sponsorship of the
    Association of American Plant Food Control Officials (AAPFCO) and The Fertilizer Institute (TFI).
    TFI asked AAPFCO to assume administration of the program in 1971. It continues to function under this arrangement today. In addition,
    W. R. Grace & Company agreed to subsidize the program by furnishing statistical evaluations of the data through its statistician,
    Edwin Glocker. This continued until the death of Ed Glocker in 1989. The statistical evaluations continue via an independent
    statistical consultant engaged by the Magruder Committee.


    The Magruder Program is administered by a committee appointed by the President of AAPFCO. Membership is balanced between control
    officials and industry representatives, with six members from each sector. This is the only AAPFCO committee which permits industry
    representatives to hold full committee privileges, including holding committee offices and voting. The committee sets subscription
    fees, selects the samples comprising the series, contracts with a commercial laboratory to prepare and distribute samples, retains
    a consultant statistician, and authorizes educational programs.

    Current Programs

    Each subscribing laboratory receives one or two, (5 to 6 ounce, 142 to 170 gram) samples each month. Each month's samples contain the
    primary plant nutrients N, P and K, and about four samples each year contain secondary and minor nutrients, as well as contaminants of
    interest. Samples are analyzed by methods chosen by the individual participating laboratories. Their results, with designation of method
    used, are reported directly to the statistician. A comprehensive statistical report is prepared noting inter-laboratory bias, precision and
    accuracy for each method and analyte, and ranking of coded individual laboratories. These reports are sent to the subscribers to allow
    them to evaluate their performance. Laboratories are identified only by a confidential number, one being assigned to each subscriber.
    Individual laboratory performance is held in strict confidence.

    Interorganizational Cooperation

    The Magruder Program objectives and goals are those of AAPFCO , AOAC International, and TFI. In turn, each of these organizations
    strongly supports the Magruder Program. The methods designated on reports are those of AOAC International. TFI supports the
    program by printing and mailing the monthly statistical reports.


    There are around 100 laboratories subscribing to the Magruder Program. Most of the state laboratories in the United States are participants.
    The remaining number are about equally divided between commercial and industrial laboratories on all continents except Antarctica.

    Quality Assurance

    Interlaboratory evaluation of methods of analysis and personnel performance is increasingly important in the modern laboratory.
    Instrumentation in laboratories is a great time saver, but needs careful control. Both precision and accuracy should constantly be
    monitored by every laboratory. These areas can be improved by an Interlaboratory statistical evaluation of your laboratory. The
    Magruder Program offers this service to all organizations involved in fertilizer analysis.

    Magruder Check Sample Committee

    Appointments through 2015

    Ametra Berry
    Georgia Dept of Ag
    Kerry Cooner
    Agrium U. S. Inc.
    Michael Hojjatie
    Tessenderlo Kerley
    Patricia Lucas, Sec.
    Florida Dept of Ag
    Terrence Field
    Canadian Food
    Teresa Grant
    NC Dept of Ag.
    Hugh Rodrigues
    Thornton Labs
    Brian White
    CF Industries
    Appointments through 2016

    Gregory Haberkost
    Lebanon Seaboard
    Bill Hall, Chairman
    Keith Wegner, Vice Chair
    CO Dept of Ag
    Sharon Webb
    University of Kentucky
    Appointments through 2017

    Rhonda Boles
    University of Missouri
    Harold Falls
    CF Industries
    Barbara James
    PCS Phosphate
    Victoria Siegel
    Office of IN State
    Magruder Contacts
  • Robert A. Coelho, Statistician
  • Jamey Johnson, Treasurer

  • Robert Kieffer, Able Laboratory, Sample Preparation
  • Kerry Cooner, Web Site Administrator

  • Other Links:

    The Association of American Plant Food Control Officials AAPFCO

    The Association of Fertilizer and Phosphate Chemists AFPC

    The Fertilizer Institute TFI

    AOAC, Intl.
    last updated November 22, 2014