Soil Test Levels in North America: The 2015 Survey

In 2015, the International Plant Nutrition Institute (IPNI) will be conducting its eleventh summary of soil test levels in North America. IPNI acknowledges the past participation of the following list of public and private soil testing laboratories, which has allowed this survey to continue to grow.

When is the survey? The survey will begin in July, 2015.

How extensive is the survey? Sixty public and private laboratories participated in the 2010 summary, providing data for approximately 4.4 million samples. The labs that participated in that summary are listed below.

Private LaboratoriesA&L Analytical Labs, Inc. - Memphis, TN; A&L Canada Laboratories, Inc. - London, ON; A&L Eastern - Richmond, VA; A&L Great Lakes Labs, Inc. - Fort Wayne, IN; Agri-Food Laboratories - Guelph, ON; AgriQuanta - St-Ours, QC; AGVISE Laboratories - Northwood, ND; ALS Laboratory Group - Saskatoon, SK; Brookside Lab, Inc. - New Knoxville, OH; Dellavalle Laboratory, Inc. - Fresno, CA; Frontier Labs - Clear Lake, IA; Laboratoire Géosol - Mont St-Hilaire, QC; GMS Laboratories - Cropsey, IL; La Coop fédérée - Longueuil, QC; LGI - Ellsworth, IA; Litchfield Analytical Services - Litchfield, MI; MDS Harris - Lincoln, NE; Midwest Laboratories, Inc. - Omaha, NE; Midwest Laboratories Canada - Calgary, AB; Olsen’s Ag Lab - McCook, NE; Precision Agri-Lab - Madera, CA; Rock River Lab - Watertown, WI; Servi-Tech, Inc. - Amarillo, TX; Servi-Tech, Inc. - Dodge City, KS; Servi-Tech, Inc. - Hastings, NE; SGS Alvey Laboratory, Inc. - Belleville, IL; SGS MWSS, Inc. - Brookings, SD; Spectrum Analytic, Inc. - Washington Court House, OH; SURE-TECH Laboratories - Indianapolis, IN; Ward Laboratories, Inc. - Kearney, NE; Western Laboratories - Parma, ID; William Houde, Ltd. - St-Simon, QC.

Public LaboratoriesAuburn University; Clemson University; Colorado State University; Department of Natural Resources Corner Brook, NL; Iowa State University; Kansas State University; Kentucky Division of Regulatory Services Michigan State University;
Mississippi State University; New Brunswick Agriculture & Aquaculture; New Mexico State University; North Carolina Department of Ag; North Dakota State University; Nova Scotia Department of Agriculture; Oklahoma State University; PEI
Soil & Feed Testing Laboratory; South Dakota State University; Texas A&M University; The Pennsylvania State University; University of Arkansas; University of Connecticut; University of Delaware; University of Florida; University of Georgia;
University of Guelph; University of Maine; University of Missouri; University of New Hampshire; University of Tennessee; University of Vermont; University of Wyoming; Virginia Tech.

What information is gathered? Each laboratory is asked for:

• the number of samples falling within certain soil test ranges for phosphorus (P), potassium (K), pH, magnesium (Mg), chloride (Cl), sulfur (S), and Zinc (Zn)
• the above data for each state or province.

How does IPNI use the data it gathers?Data from all participating laboratories, both public and private, will be merged for each state or province. All laboratory specific data are considered confidential and are not released to the public or any other entity.

IPNI creates two publications from the summary:

• the IPNI Bulletin, Soil Test Levels in North America
• an article in the IPNI Better Crops magazine

The information in these publications includes graphics like those shown

Relative frequency of P levels for North America during various survey years (Fixen et al., 2010. Better Crops 94(4):6-8)

Median soil test K levels in 2010 for states and provinces with at least 2000 samples reported (Fixen et al., 2010. Better Crops 94(4):6-8)