Mid-Atlantic Soil Testing and Plant Analysis Workgroup
Southern States Cooperative building in Richmond, VA
April 30 - May 1, 2003, (postponed from February 19-20 due to a snow storm)
Wednesday, April 30, 2003
The meeting was called to order by the chairman, Kathy Moore. Attendees introduced themselves.
Ann Wolf presented the results of the group's Manure Sample Exchange, (see handout). A total of nine labs participated, performing three replicates on each of a Dairy, Swine, Poultry-layer, and Poultry-broiler sample. One liter of sample was frozen and shipped overnight on ice. Overall results were impressive. The best RSDs were on the % solids for the poultry samples. The swine sample was the most variable within a lab and between labs, though swine was pretty tight on total K. Though performed on a dry weight basis, the soluble P Test still needs additional attention. With the new national Manure Analysis Proficiency (MAP) testing program, perhaps the MASTWG participates can perform and compare their data for the soluble P test on the second quarter samples in August.
8:53 a.m. Ann Wolf also talked about the now completed Manure Manual which was six years in the making with the last year in editing at Wisconsin, and is now available only as a web publication at http://www1.uwex.edu/ces/pubs/pdf/A3769.pdf. The Soluble P test is not included since it is a preliminary method, but is available from Ann.
8:58 a.m. Mark Flock reviewed the Amino Sugar Soil Test or the Illinois N Test. A simple (at least in equipment with 85 cent mason jars, etc., and thus also dubbed the "Wal-Mart" test) diffusion method, mineralized nitrogen test for detecting unresponsive sites and supposedly better than the PPNT or PSNT in predicting available N. Information on this test is available at the web site, http://frec.cropsci.uiuc.edu/2003/. A one gram air-dried and ground soil sample is used along with NaOH and an ammonium trap. Sample and test from the end of harvest to planting. Results are slightly higher in the spring. A five hour test; doing 20 samples per day. One drop of titrant corresponds to 20 ppm N. A sample to a six inch depth testing greater than 250 ppm means no response to nitrogen.
Overall, Mark's experience is not off to a good start. It doesn't seem to be a rigorous method with too much variability from day to day. Jar bottoms cracking from drops of condensation, especially with high organic matter samples. Uniform heating is essential.
The group thought that this is a test that's being used in applied, public service labs before it should have left the research labs.
9:52 a.m. Break - refreshments courtesy of Southern States.
10:20 a.m. Bob Miller compared the Means and MADs of last year's NAPT samples with a subset of statistics for just the Mid-Atlantic labs. He gave updated comparisons for phosphorus by various methods, M3-P color vs. ICP and Bray P1 by color vs M3-ICP.
By looking at the RMDs, (Relative Median Deviation = MAD/median x 100), of inter-laboratory test results, Bob identified the best and the worst performing methods that are reported in the NAPT program. For a tight analysis, such as pH, NO3-N, or TOC, the NAPT program will start using a minimum MAD value of 4% of the median, resulting in a minimum 90% Confidence limit of ± 10% of the median.
Bob mentioned three other programs:
the US Composting Council, http://www.tmecc.org/;the Manure Analysis Proficiency Testing Program (MAP), which currently has an EPA grant and sends out 3 sets of samples per year; and the Greenhouse and Nursery Media (GNMAP) at CFU also with 3 sets of samples per year.
Bob gave a picture tour of labs down under in Australia and New Zealand which included a talk about "Rosie" a soil scooping and extracting robot which can process 60 samples per hour. Rosie works at Hill Laboratories in Hamilton, New Zealand.
Bob mentioned the success of the 8th International Symposium on Soil and Plant Analysis (ISSPA) held last January in Somerset West, South Africa, and promoted the coming 9th ISSPA meeting to be held in Cancun, Mexico, Jan 31 - Feb 4, 2005 of which Mark Flock is the chair of the Planning Committee. Probable topics include Defining Measurement Uncertainty, Carbon Sequestration, and Turf Grass Analysis & Interpretation. [http://www.spcouncil.com/]
11:15 a.m. Ann Wolf started a discussion regarding measuring soil acidity. The University of Maryland, Penn State, and Virginia Tech labs are all looking into using the Mehlich buffer. The University of Georgia is considering a titration method.
11:33 a.m. Phil Howard gave an update of Southern States' activities. SSC is excited about the new Farm Bill. Southern States is using zone rather than grid sampling, and having trouble getting farmers to take the time to use Yield Monitors.
11:50 a.m. Lunch was provided by Southern States.
1:00 p.m. Regarding the titration study for acidity, Karen Gartley said to look for results to be e-mailed around June.
1:05 p.m. David Kissel talked about University of Georgia's efforts to measure soil acidity. Their current Adams-Evans buffer pH is not doing a good job on soils with a low (<5) CEC, and they are looking into a titration method of adding Ca(OH)2 to a 1:1 water:soil mixture using representative Ag soils for Georgia. Showed how Ca(OH)2 titration curves of soils in both water and 0.01M CaCl2 are about the same when the difference between these two pHs can be as much as 2 pH units at some times of the year. Got good agreement in Lime Requirement comparisons between 2 point prediction in 0.01 M CaCl2 titrations and 3 day Ca(OH)2 incubation. Said that a 3 day incubation is better than a 6 month time frame because the 6 month period is confounded by nitrogen mineralization.
1:52 p.m. Carl Crozier summarized North Carolina's programs and experiences in Precision Ag. The Research side is mainly doing problem diagnosis using GIS. Teaching is offers a GIS minor or certificate, and Extension gives field days and conferences. There is the potential to use aerial photos to prescribe optimum N sidedress rates for corn and in managing PIX in cotton (slow the growth to give more flowering). See the handout entitled, NCDA, Soil Sampling for Precision Farming Systems, and the web sites, http://www.precisionag.ncsu.edu/index.htm, and http://www.ncfloodmaps.com/.
2:45 p.m. The group went to A&L Eastern Agricultural Laboratories, Inc. at 7621 Whitepine Road in Richmond where Paul Chu gave a tour of their facilities.
5:30 p.m. The evening social was provided by Ted Hess of Spectro Analytical Instruments, Inc., http://www.spectro.com.
6:45 p.m. The group ate dinner at the Stake & Ale courtesy of Ras Erasmus of LabFit, Burswood, Western Australia, http://labfit.highway1.com.au.
Thursday, May 1, 2003
8:27 a.m. Bob Miller brought up that the EPA grant for the MAP stipulated that 7 workshops be conducted in 2 years. These would be laboratory workshops with emphasis on manure analysis, sample & data handling, lab quality and instrumentation, and 12 to 15 participants would be needed per workshop. Several possible times to hold one of these workshops on the east coast were brought up with the favorite being to hold one in the last week of April 2004, possibly in Raleigh, NC. Another workshop would probably also be held in the Northeastern part of the U.S.
Bob also brought up how soil analysis is evolving from a tool for predicting nutrient supply to environmental assessment, and how NRCS wants an accreditation standard. Regardless of the progress of the NAPT program over the past 5 years, there is a perception that quality of soil analysis labs is not up to the standard, and if we, the industry, don't do something, then someone else will. A handful of labs in the west are pushing for either a certification or an accreditation of labs. Phil Howard mentioned that a TSP's, (Technical Service Provider's), liability when writing Nutrient Management Plans will cause them to use only accredited labs. Bob proposed the idea of using Double Blind samples, where samples with unknown values to the lab are also sent in to the lab from a surrogate source that is indistinguishable from any other client's sample; as opposed to the lab knowing that the sample came from a certifying/accrediting agency. Labs in the West want this, and SSSA is willing to help.
9:12 a.m. Ras Erasmus spoke about LabFit's offerings in instrument automation: the AS-3000 pH & Conductivity Analyzer, the AS-3000 Weigh Master, the CS-2000 Carbon & Sulphur Determinator, and the AG-3000 (orbital) Sample Stirrer. [see http://labfit.highway1.com.au]
9:40 a.m. Web Reporting and New Instrumentation:
Ann Wolf - In an effort to get away from Kjeldahl determinations of N for manure and sludge, Penn State purchased a vario MAX combustion instrument from ELEMENTAR. [see http://www.chnos.com/] Unlike comparable instruments, elementar's instrument can handle a large (1/2 to 1 gram) sample and has an autosampler that works well. They do runs overnight with no problems. The vario MAX uses 5 ml, reusable, stainless steel crucibles. They add acetic acid to high pH samples.
Bob Miller - HACH bought Latchet Instruments about a year ago.
9:?? a.m. Break - refreshments courtesy of Southern States.
10:13 a.m. Laboratory Reports:
Brookside - Mark Flock reporting: Samples down 5%. Dealing with turn-over in personnel. Bought a used ICP and GC-MS. Hired a GIS specialist to work in the field.
University of Delaware - Karen Gartley reporting: Not a whole lot of change besides a big reduction in their budget. Want to buy an Elementar. Tom Sims is working on P issues and with SSSA President-Elect duties.
Delaware Dept of Agriculture - Bruce Tribbitt reporting: The State of Delaware has a new manure analysis lab with no charge for testing at this time. Samples are mainly coming from the conservation district and consultants and not directly from farmers. All manure types and compost are tested. Tested 210 manure samples in 2003. Minerals are microwave digested followed by quantification with a P-E ICP. Nitrogen analyses are performed using Kjeldahl and combustion methods. They also test for total carbon and carbon/nitrogen ratio for compost. Carbon is analyzed using an Elementar combustion analyzer.
University of Maryland - Joe Buriel reporting: This Past Year -- Starting January 1, 2003, our prices for regular soil test package went up to $8.00. (Previously, $5 and $6.) The lab will not bill for less than $100. Regular test package includes: Water pH, hand texture, available Mg, P, K, Ca and % OM. The lab ran about 25,000 soil samples. This is about a 4% decrease from the previous year. There were 1,822 manure samples run for Maryland clients under the Nutrient Management Program. This was about an 18% decrease from last year. Plant samples numbered about 7,000, about 75% over last year's numbers. Over past 2 years, 2 technician positions are pending due to budget cuts. Major Developments and Future Happenings -- Integration of microwave digestion using Nitric Acid into our plant and manure analysis program. Switching to Mehlich III extractant and ICP analysis for soil samples during the summer of 2003. Researching the use of Mehlich Buffer for lime requirement.
Virginia Tech - Steve Heckendorn reporting: Received around 40,000 soil samples for 2002, which is about a15% decrease from the year before. This past fall & spring samples were down 30% from the previous seasons. Ordered a second AS-3000 automated pH analyzer from LabFit, which will help add the Mehlich buffer this year. With Steve Donohue's retirement, Greg Mullins is now serving as the faculty liaison for the lab. Our department lost a total of 7 faculty members last year, 4 of which had Extension appointments. We have a new department head, (Steve Hodges), an interim College Dean, and a new Extension Director.
Agri Analysis - Tim Hoerner reporting: Samples are also down. Putting a concentrated effort in value added sales. Aggressively pushing Tissue Testing. NIR is a primary money maker; will try to build a database this summer of NIR spectrum scans of corn.
Spectrum Analytic - Vernon Pabst reporting: Overall, business is down 20 - 25% with the number of soil samples being flat and lime samples up. Added a used TJA ICP.
Land O Lakes (Sure-Tech) - Jodi Gessner reporting: Steady number of samples with ~200,000 soils per year. Set a one day record of 6,280 samples last October. Have 4 full-time staff. Have a new grinding area, and are updating custom software, computers, and servers.
Penn State - Ann Wolf reporting: Soils samples are down 25 - 30% this year. Purchase of an Elementar N/C analyzer which is currently being used for manures and composts. Plan to work with DEP to determine if it can be used for sewage sludges. Expansion of Compost Testing Program. Web site expanded - view reports and 3 years worth of data on-line. Ability to make on-line change to soil recs for new crop; there's now a charge for the lab to do this. County agents think it's great; no more hard copies. The lab now has a credit card option. [www.aasl.psu.edu] Will be evaluating Mehlich buffer test in comparison to SMP on PA soils. Working with USDA ARS on P Index issues. Development of soluble P test for manure. Dick Fox retired which will severely limit our N research. Evaluating alternative chlorophyll meter N test approach. New project on Amino Sugar N Test for corn. Starter fertilizer on high P soils - third year of 20+ on farm trials with no starter, normal starter, N only starter. Finishing grass N, P, K fertilization studies.
A&L - Paul Chu reporting: Fall soil sample volume down 40% from 2001. Spring sample volume is also down the same percentage. Use a MARS (from CEM) microwave digestion for plant (open high throughput) and sludge (close high pressure) samples. Noted that Al & Fe values are lower in an open system. Expressed concerned about state labs using different index values to report results.
Clemson - Kathy Moore reporting: New AS-3000 purchased last June. New Spectro Ciros radial ICP purchased by our Regulatory Department. Changing to a bag for soil samples. Totals: Soil - 35,000; Plant - 2,500; Feed, - 1,800; Water - 600; Waste - 1,200; Solutions - 3,500.
US Borax - Jim Woodruff stated that 1978 was the start of MASTWG in order to get state labs to give uniform recommendations. Jim went through his handout entitled, Diagnostic Interpretations from Insignificant Data; A Useful Approach to Documentation, showing that if data were examined in other ways, such as by use of linear or curvilinear regression and curve-fitting, then we can often find significant relationships among previously assumed non-significant results.
The Soil Testing Section analyzed 307,474 samples, which is down by about 4.5% as compared to the previous year. Agricultural crops predominate the sample volume with cotton accounting for about one-third of all samples.
A new Thermo-Electron 61E ICP was placed on-line in the summer of 2002. Modification to our drying system also occurred over the summer. The section continued evaluation of the AS3000 Labfit pH Analyzer and placed it on-line to read water pH. The lab is continuing to look at automation and is working with an engineering firm to design an automated humic matter station. A new soil box (shorter and perforated top for easy removal) was tried on a temporary basis but it was not viewed to be an improvement so the change was not made. The lab did participate in the NAPT program for the first time and viewed it to be a helpful addition to the QA/QC efforts.
State budget concerns in NC continue with possible fee proposals. A soil fee of $3.00 per sample was proposed in 2002 but the bill was "killed" in the final budget. The lab did lose one position in the budget crisis.
The Plant / Waste / Solution Section analyzed 37,509 samples during the 2001-2002 fiscal year. Of these samples, 16,935 were plant tissue analysis. Cotton, trellis tomato, strawberry, flue-cured tobacco, and bentgrass represented crops analyzed in the greater amounts.
Animal agriculture in North Carolina accounted for the majority of waste samples analyzed (18,460). More than 11,500 samples were processed from swine industry alone. Greater than 2,500 samples came from the poultry industry.
Plans for the 2004 meeting:
- Next year's meeting will be February 18-19, 2004 with snow dates of April 28-29. (These dates have been confirmed since the meeting.)
- Soluble P
- Index Values
- Acidity measurement updates; Mehlich buffer and titration methods
-Virtual tour of a lab
The meeting was adjourned at about 11:45 a.m.
Minutes submitted by Steve Heckendorn