A Review of the Pennsylvania Phosphorus Index ... - PennFuture

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Thus in this example, the allowable application rate of manure P was sensitive to the PSC value.While no centralized repository of PSC values are available for review, based upon a personalcommunication with Dr Beegle, the WEP-based PSC values he has seen are quite a bit lowerthan the Book values. According to Dr. Beegle, the PSC Book values were set at the upperbounds of the expected PSC values so it was not surprising to him that the WEP-based PSCvalues were lower.140Allowable Manure Phosphorus(lbs P2O5/A)1201008060402000.8 (H) 0.6 (M) 0.4 (M) 0.2 (M)Phosphorus Solubility Coefficient (P-Index Rating)Figure 1. An example of the influence of the Phosphorus Solubility Coefficient on the allowableapplication rate of manure phosphorus. This example is adapted from Beegle et al (2009),Appendix 5, Scenario 3. The conditions are summarized in Table 1.Page 5
Table 1. Conditions assumed in example displayed in Figure 1. (Adapted from Beegle et al(2009)Soil Test Levels (Mehlich-3) 201 ppm PCrop; Planned YieldCorn; 125 bu/AOther P Nutrient Applied 0Manure Group: Application Dairy; SpringSeasonN Balanced Manure Rate 11,905(gal/A)Planned Manure Rate (gal/A) 9000*Manure Nutrients Applied at 76 lbs N; 117 lbs P #Planned Rate (lbs N or P)Fertilizer Application Method 0.2Factor: Placed or injected 2” ormore deepManure Application Method 0.6Factor: Incorporated >1 week ornot incorporated followingapplication in April to OctoberPhosphorus Source Coefficients 0.8, 0.6, 0.4, 0.2Erosion Factor: Soil Loss 4(ton/acre/yr)Runoff potential Factor: 6Drainage class is somewhatpoorSubsurface drainage: none 0Contributing Distance: 100 to 6199 ft. or
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A Review of the Pennsylvania Phosphorus Index ... - PennFuture

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