The Missouri Soil Testing Association Accreditation Program (MSTA) is designed to assure that results provided by participating public and private labs serving the citizens of Missouri agree with allowable statistical limits. Based on this premise, soil test results from MSTA-approved labs will be accepted by the U.S. Department of Agriculture and Farm Service Agency (FSA). Beginning in 1999, MSTA combined its efforts with the North American Proficiency Testing Program (NAPT). The NAPT coordinator sends soil test data from the labs participating in MSTA program to the state coordinator. The MU Soil Testing Lab director serves as the state program coordinator and performs statistical analysis of the data as specified in the MSTA program. If a lab's results fall within the allowable limits, the lab will be placed on the Farm Service Agency's (FSA) list of approved labs. A lab that is not accredited may re-apply after one year.
See list of approved labs below.
Approval procedures for MSTA labs
The labs that wish to participate in the MSTA program should send a formal written request to the director of the MU Soil Testing Lab. They also need to request the NAPT coordinator to release their results to the MSTA program coordinator by signing a "Missouri Release" form when they sign up for NAPT.
Participating labs must use procedures of the Missouri Soil Testing Program in current use as described in the University of Missouri Extension Guide Soil Testing in Missouri (EC923).
The lab will be approved for routine soil tests:
- Bray-I P; ammonium acetate extractable K, Ca, and Mg
- Organic matter
- pH in 0.01 M CaCl2
- Neutralizable acidity (using the Woodruff Buffer test)
Standard pH 7.0 and pH 4.0 buffers must be used to calibrate all pH meters.
It is suggested each laboratory set up two or more internal check samples. One of these checks should be included with each twenty or thirty soil samples. A log of the results of the check samples should be maintained.
The MSTA coordinator will receive results from the NAPT program coordinator on the recommended tests and do the statistical evaluation.
Approval criteria for MSTA labs
The MSTA program uses the median and median absolute deviation (MAD) as used by the NAPT program as robust estimations of central values and variances of all data sets. This statistical approach is less sensitive to influence of extreme values (outliers) than the mean and standard deviation. The MSTA summary report lists the median and MAD values and the lab data. If the lab's data falls outside the range of +2.5x MAD (it is marked as Low or High) and considered to be out of the allowable limit. If the lab data falls outside the limits of +3.5x MAD they are marked as outliers.
Test results of 75 percent of the samples must fall within the above allowable limits for each test. Upon meeting these criteria a letter will be sent to FSA to add the requesting lab to the list of approved labs in Missouri. If a lab doesn't meet the criteria to be approved, contact the MU Soil Testing Lab director for a second chance for approval by analyzing five unknown samples sent by the MSTA program.
Missouri state approved labs
August 1, 2024 to July 31, 2025
Based on all four quarters of sample exchanges, 2023.
Missouri
- MU Soil and Plant Testing Lab
University of Missouri
23 Mumford Hall
Columbia, MO 65211
Phone: 573-882-3250 - Perry Agricultural Lab
PO Box 418
State Highway 54 East
Bowling Green, MO 63334
Phone: 573-324-2931
Georgia
- Waters Agriculture Lab
257 Newton Hwy, PO Box 382
Camilia, GA 31730
Phone: 229-336-7216
Illinois
- Waypoint Analytical Illinois, Inc.
2906 W. Clark Road
Champaign, IL 61822
Phone: 217-359-7680
Indiana
- A&L Great Lakes Laboratory, Inc.
3505 Conestoga Drive
Fort Wayne, IN 46808
Phone: 260-483-4759
Iowa
- Ag Source Laboratories
1532 Dewitt
Ellsworth, IA 50075
Phone: 515-836-4444 - Waypoint Analytical Iowa, Inc.
111 Linn St.
Atlantic, IA 50022
Phone: 901-213-2400
Kentucky
- Waters Agriculture Lab
2101 Old Calhoun Road, Hwy 81
Owensboro, KY 42301
Phone: 270-685-4039
Minnesota
- MVTL Laboratories Inc. – New Ulm
1126 North Front St.
New Ulm, MN 56073-0249
Phone: 507-354-8517
Nebraska
- Midwest Laboratories, Inc.
13611 B St.
Omaha, NE 68144-3693
Phone: 402-334-7770 - Ward Laboratories
4007 Cherry Ave.
PO Box 788
Kearney, NE 68848
Phone: 308-234-2418 - American Agricultural Laboratory, Inc.
700 W D Street
McCook, NE 69001
Phone: 308-345-3670
Ohio
- Brookside Laboratories, Inc.
200 White Mountain Drive
New Bremen, OH 45869
Phone: 419-977-2766 - Spectrum Analytical
1087 Jamison Road
PO Box 639
Washington Court House, OH 43160
Phone: 740-335-1562
Tennessee
- Waypoint Analytical, Inc.
2790 Whitten Road
Memphis, TN 38133
Phone: 901-213-2400
Wisconsin
- Ag Source Cooperative Services
106 N. Cecil St.
PO Box 7
Bonduel, WI 54107
Phone: 715-758-2178