Minutes of the 2009 Mid-Atlantic Soil Testing and Plant Analysis Work Group Meeting

The meeting was called to order at 8:15 a.m. on February 17, 2009 by Leticia Sonon and Dave Kissel of the University of Georgia. The group of 26 participants was welcomed to the 2009 meeting and introduction and housekeeping were made. Phil Howard of Southern States, the host agency, gave an update on Southern States including current fertilizer issues on supply, demand and cost. After Phil's updates, a series of papers covering a wide array of topics were presented. Summaries of some papers and the complete program of activities are given below.

The group also discussed plans for the 2010 meeting including dates and possible topics:

The group was encouraged to suggest additional topics to consider for the 2010 meeting and send these to Leticia or David. The meeting adjourned at 12:00 pm on February 18, 2009.

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PAPER SUMMARIES

Carl Crozier of North Carolina State University gave a presentation on N, P Availability and Liming Effect of Poultry Litter Manures. A 90 d incubation compared N mineralization from manures and urea. Mean availability in the Belhaven and Lynchburg soils was 76, 73, and 55% of total N applied in fresh, composted, and pelleted manures, respectively; whereas N availability in the Cecil soil was 41, 33, and 27% for the same manure sources. A 21 d lime incubation found liming materials in all manures just as effective in neutralizing soil acidity as equivalent amounts of CaCO₃. A 21 d P incubation found similar changes in Mehlich-3 extractable soil P resulting from application of equivalent amounts of either manure or inorganic P.

David Kissel of the University of Georgia presented data from a graduate student's thesis of the rate at which calcium hydroxide applied to acid soils reacts with acidity and reaches pH equilibrium. The intent of this work was to develop an improved method for calculating the lime requirement from single addition titration with calcium hydroxide, the method used at UGA for lime requirement determination. The majority of soils reached equilibrium within 25 hours whereas others required more time. It appeared that there was a quantitative relationship between the lime buffer capacity determined with 30 minutes equilibration and the lime buffer capacity with 84 hr equilibration.

Bob Miller gave a paper on evaluation of grinding soil particle size for Bray-P1 and ammonium acetate K for four soils. Bob found that highest variability (based on RSD) was for 2.0 mm relative to 1.0 and 0.5 mm. RSD values for Bray P1 ranged from 1.8 to 4.8% across the 4 soils, and there was no significant bias in analyte concentrations with reduced particle size. A comparison of soil grinders found a hammer mill and Agvise Grinder provided the most homogenous samples with respect to Bray P1 and Ammonium acetate K.

Ann Wolf - Penn State has now purchased two Autoblock Digestion systems from Environmental Express. The blocks are used for digesting soil, plants, maures, biosolids, composts and water. The blocks are working well and have significantly improved the efficiency of sample digestion.

David H. Hardy, Soil Testing- Agronomic Division, NC Dept. of Agriculture and Consumer Services, talked about "Experiences with PSNT in North Carolina". He indicated that over the past five years, the PSNT test in corn was studied in several field locations (5 trials) on Piedmont soils with a history of broiler litter application. On a wet on basis, an average of 29 lb of available N was supplied by litter and typically 4 to 6 tons per acre was used by growers. Use of the PSNT at approximately 25 ppm soil NO3-N in determining the need for side-dress N (V5.growth stage) was successful in these trials. There is further need to evaluate this test on a wider variety of soil under different N management regimes for its usefulness to NC growers.

Leticia Sonon presented a paper on the evaluation of 1.5 multiplier for lime requirement to account for aglime that is less reactive than reagent grade CaCO₃. Although research has been conducted with aglime to arrive at this efficiency factor, it has not been conducted using Georgia soils or with aglimes available in Georgia that may differ in their reactivity and purity from others tested previously. The efficiency of five aglimes commercially marketed in Georgia was compared to reagent-grade CaCO₃ powder on two GA soils with different chemical properties and lime buffering capacities (LBC). Both soils exhibited an overall increase in pH over the 12-month incubation period, but pH also increased in low LBC soil with no aglime treatment (control). Overall, the final pH values were higher in low LBC soil than high LBC soil. Further evaluation of aglime efficiency factor in high LBC soil indicated multipliers of 1.17, 1.16, 1.48, 1.34, and 1.73 for aglimes 1 through 5, respectively, with an average multiplier of 1.38. For practical purposes, a multiplier of 1.5 is suggested.

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PROGRAM OF ACTIVITIES

Mid-Atlantic Soil Testing and Plant Analysis Work Group Southern States Building, Richmond, VA February 17-18, 2009 PROGRAM
Tuesday, February 17, 2009 Morning Session
8:15 - 8:30	Welcome, Introduction and Housekeeping
8:30 - 8:50	Update from Southern States
8:50 - 9:15	Carl Crozier - N, P Availability and Liming Effect of Poultry Layer Manures
9:15 - 9:40	David Kissel - Upcoming Changes in UGA Titration Method for Lime Requirement
9:40 - 10:00	Break - Complimentary Snacks by Southern States
10:00 - 10:25	Frank Sikora - Unified Analysis of Buffer Methods for Lime Requirement
10:25 - 10:50	Bob Miller - Soil Grinders and Laboratory Results
10:50 - 11:15	Leticia Sonon - Aglime recommendations: the 1.5 Factor for Lime Quality
11:15 - 11:30	General discussion
11:40 - 1:00	Lunch - Sponsored by Southern States
Afternoon Session
1:10 - 1:35	David Hardy - Experiences with PSNT in North Carolina
1:35 - 2:00	Brenda Cleveland - Blackberry Plant Tissue Monitoring Nutritional Status in New Cultivars (Given by David Hardy)
2:00 - 2:20	Paul Chu - Cutting Costs in the Lab
2:20 - 2:40	Ann Wolf - AutoBlock Digsetor for water/soils/plants/manures/composts/biosolids
2:40 - 3:00	Break - Complimentary Snacks by Southern States
3:00 - 3:15	Bob Dussich - Spectro Instrument Update
3:15 - 3:30	Bob Isaac - LabFit Update
3:30 - 4:00	Vernon Pabst - Virtual Tour Spectrum Analytic Labs
4:00 - 4:15	Brian Taylor (ROSeee Instruments) - Automation of soil sample preparation - scooping, weighing, extracting, beaker cleaning and drying, filtering
4:15 - 4:30	Keith Hensley - Lignin Update
4:30 - 4:45	Sandy Hughes (Elementar Americas) - TOC of soils with automatic feeding
5:00 - 6:00	Break - hotel bound
6:00 - ????	Dinner
Wednesday, February 18, 2009 Morning Session
8:15 - 8:40	Solomon Kariuki and Josh McGrath - Quantification of Trace Metals in Biodesel
8:40 - 9:05	Noble Usherwood - Biofuels
9:05 - 9:30	Bill Segars - Soil Fertility Questions on the CCE Exam
9:30 - 9:45	Mike Black, Thermo Scientific
9:45 - 11:00	Discussion, Planning, State Reports

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Acknowledgement

The group thanked Southern States and Phil Howard for their kindness and unceasing support in hosting the Mid-Atlantic Soil Testing and Plant Analysis Work Group, and sponsors for sharing their resources including updates on instrumentation and technology.