1. Effects of various soil amendments on soil test P values David Brauer, Glen Aiken, Dan Pote ARS/USDA, Booneville AR S.J. Livingston, L.D. Norton ARS/USDA, W. Lafayette IN T.R. Way and J.H. Edwards ARS/USDA, Auburn, AL

2. Acknowledgements Additional funds were provided by: –Southern Plains Area Office/ARS –U.S. Poultry and Egg Association

3. Rationale and Objectives Rationale –Manure applications from concentrated animal feeding operations have increased soil P levels –P transport from agricultural land to surface water is undesirable Objectives –Evaluate various amendments to decrease soil test values for P

4. First Experiment-Kurten TX

5. Farm History- Kurten Site Farm occupies 200-300 acres Dairy operation- Post WWII era (30 years) Hen laying operation since early 1980’s –500,000 birds –30-35 Mg of wet manure produced daily (70% moisture)

6. Aerial view of Kurten Site

7. Kurten TX site: Climate Rainfall –About 900 mm of annual rainfall –About 100 mm occurs in July and August, thus leading to low soil moisture Annual Average temperature –About 20 C

8. Kurten Site- Soil Characteristics Zulch fine sandy loam (thermic udertic Paleustalfs) Chemical characteristics Ap horizon –Mehlich III P~1,500 mg/ kg –Bray-1 P~3,000mg/ kg –DRP (25:1) 50mg/ kg –Soil Ca~5,500mg/ kg –Soil pH 7.8

9. Soil amendments at Kurten Site Gypsum (2 rates, 1.5 and 5 Mg/ ha) Alum (1.4 Mg/ ha) Waste paper (24.4 Mg/ ha) Waste paper plus Gypsum Waste paper plus Alum Waste paper plus Alum and Gypsum

10. Experimental Protocol Amendments applied annually 1999 to 2001 in March. Soil samples (0-7.5 cm and 7.5-15 cm) collected in July/August from 1999 to 2004. Bray-1 P and DRP (25 ml water per 1 g soil). DRP solutions analyzed for Ca-readily reactive Ca.

11. Ca and Al additions (kg/ha) Annual AmtTotal Amt CaAlCaAl 1.5 Mg Gypsum/ha 3501,050 5 Mg Gypsum/ha 1,1603,580 1.4 Mg Alum/ ha 130390 22.4 Mg Paper/ha 100300

12. Bray-1 P (Means for 1999-2001)

13. Soil DRP (Means for 1999-2001)

14. Changes in Soil DRP with time

15. Changes in “reactive”soil Ca with Gypsum from 1999 to 2001

16. Rainfall Simulation Data (Livingston et al. 1999)

17. Booneville Experiment Ability to change soil P levels with waste paper Leadvale silt loam Low P soil (<60 mg P/kg Bray-1 P values) 3 rates of waste paper (22, 44 or 88 Mg/ha to supply 90, 170 or 350 kg Al/ha)

18. Booneville Experimental Area

19. Waste Paper Addition on Soil P

20. Waste paper and Soil Bulk Density

21. Conclusions Gypsum can reduce runoff and DRP when soil P values are very high –Low soluble, reactive Ca –Ca added in amounts equal to Mehlich P Decreases in runoff P with amendments –Maybe associated with changes in soil structure