Agricultural Fertilizer Applicator Soil Test Results What the heck do they mean?

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1 Agricultural Fertilizer Applicator Soil Test Results What the heck do they mean? Northeast Ohio Pesticide Safety Education Program Lee Beers, OSU Extension Trumbull County

2 Soil Tests Come in All Shapes & Sizes--- Know what yours is telling you

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4 Use this report to fill out your table.

5 Value Western Reserve Penn State Desirable Range Buildup, Drawdown, Maintain How much to add? C.E.C ph Lime Lime Index/Acidity K (lbs/acre) Mg (lbs/acre) Ca (lbs/acre) P (lbs/acre) K % Mg % Ca %

6 Value C.E.C 7.9 Western Reserve Penn State Desirable Range Buildup, Drawdown, Maintain How much to add? ph 6.4 Lime Lime Index/Acidity 69 K (lbs/acre) 288 Mg (lbs/acre) 315 Ca (lbs/acre) 1996 P (lbs/acre) 57 K % 5 Mg % 16 Ca % 63

7 Use this report to fill out your table.

8 Value Western Reserve Penn State C.E.C Desirable Range Buildup, Drawdown, Maintain How much to add? ph Lime Lime Index/Acidity K (lbs/acre) ? Mg (lbs/acre) ? Ca (lbs/acre) ? P (lbs/acre) K % Mg % Ca % PPM X 2 = lbs/acre

9 Value Western Reserve Penn State C.E.C Desirable Range Buildup, Drawdown, Maintain How much to add? ph Lime Lime Index/Acidity K (lbs/acre) Mg (lbs/acre) Ca (lbs/acre) P (lbs/acre) K % Mg % Ca %

10 Meq/100g Conversion Ratios Element Factor Example Ca 400 K 780 Mg 240 Na me Ca/100 grams = 400 lbs /acre 1 me K/100 grams = 780 lbs/acre 1 me Mg/100 grams = 240 lbs/acre 1 me Na/100 grams= 460 lbs/acre

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12 Soil Chemistry: Lime Clay Particle H + H + + CaCO 3 (Lime) Ca Clay Particle H 2 O + CO 2 (water) (carbon dioxide)

13 Buffered ph or Lime Test Index (LTI) The amount of Ca or Mg found on soil particles that will control the rate at which ph changes. Numbers usually between 60 and 70 or 6.0 to 7.0. The higher the number the more difficult it will be to drop ph, but it will be very easy to raise the ph.

14 Lime Test Index

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16 Value Western Reserve Penn State C.E.C Desirable Range Buildup, Drawdown, Maintain How much to add? ph Lime Lime Index/Acidity K (lbs/acre) Mg (lbs/acre) Ca (lbs/acre) P (lbs/acre) K % Mg % Ca %

17 Soil Chemistry: Buffer What is a Buffer? Buffer: A resistance to a change in the ph. A buffer keeps things at status quo, meaning that the ph does not fluctuate wildly from high to low, and points in between. This is important to soil chemical stability. Buffering Capacity: Describes the capacity for a particular soil to resist a change in ph. The greater the buffering capacity, the more difficult it is to change the ph.

18 Soil Chemistry: Buffer Mg 2+ H+ H+ H+ H+ H+ Al 3+ - H -- Ca 2 - K - H --- Al 3 - K - H -- Mg 2 H+ -- Ca 2 Clay Particle Al 3 H Mg 2 H+ - K - H - K Ca 2 - K - H -- K+ K+H+ - K -- Mg 2 H+ H+ H+ Ca 2+ H+ OH- OH- OH- OH- OH- Al 3+

19 Soil Chemistry: Buffer High buffering capacity High ratio of hydrogen compared to other elements Means high Reserve Acidity Hard to change ph H - - Clay Particle -H H - - H - - H H K H H H H H H H H - H - Mg 2 H - H H - H - H - H - H - H - H - Ca 2 -H K - Ca K Mg 2 H - - K Mg Al Ca Clay Particle - K Al Ca 2 K - K - - H Ca Ca 2 - K - K Low buffering capacity Low ratio of hydrogen compared to other elements Means low Reserve Acidity Easy to change ph

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21 Soil Chemistry: CEC Riding the CEC Bus: Mg 2 - H - H -- - H - H H-- H - H - K - K - H - H -- Clay -- Ca 2 - Particle Ca 2 K H H K K H H H H H Mg 2 - K Passenger Seating: H =16 (16 seats) K =6 (6 seats) Mg 2 =2 (4 seats) Ca 2 =2 (4 seats)

22 Soil Chemistry: CEC Riding the CEC Bus: H- -- Ca Al 3 - K Clay - K - Particle H K - K - H - H -- Mg 2 -- Ca 2 - K -- - Al Mg 2 3 H - K - H Ca Mg 2 Passenger Seating: H = 6 (6 seats) K = 6 (6 seats) Mg 2 = 3 (6 seats) Ca 2 = 3 (6 seats) Al 3 = 2 (6 seats)

23 Soil Chemistry Common Soil Cations & Anions: Cation Chemical Symbol Ionic Form Anion Chemical Symbol Ionic Form Potassium K K + Hydrogen H H + Ammonium N NH + 4 Calcium Ca Ca ++ Magnesium Mg Mg ++ Aluminum Al Al +++ Iron Fe Fe ++ Nitrate N NO - 3 Chloride Cl Cl - Sulphate S SO -- 4 Phosphate P H 2 PO - 4 Borate B BO - 3

24 Correct ph First!!

25 Soil Chemistry: Soil Test Soil Test Results: Ideal Values ph Phosphoru s P lb/a* Potassiu m K lb/a* Calcium Ca lb/a* Magnesiu m Mg lb/a* Cation Exchange Capacity (CEC) meq/100g Base Saturation % % % Ca Mg K % - 10% - 3% plus or higher 80% (65%) 40% (15%) 5% (5%) * To convert lb/a (pounds per acre) to ppm (parts per million), divide by 2: 100 lb/a = 50 ppm

26 Nitrogen

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29 Phosphorus

30 Ohio Phosphorus Recommendation Approach BMD Approach Buildup Maintenance Drawdown Provides adequate nutrients for the current crop year and capable of providing for next year. Feed the soil concept.

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33 Field Identification Western Reserve # Penn State S (Back Cow Pasture) Current Soil Test Level #/acre Desirable Range 57 #/acre ppm #/acre 11 ppm ppm #/acre Buildup, Maintenance, or Drawdown? Maintenance Buildup

34 Fertilizer Phosphorus Source Name N Content* P 2 O 5 Content* Common* Water Solubility** ph* Rock Phosphate Triple Super Phosphate Mono-ammonium Phosphate Di-ammonium phosphate >90% Polyphosphate Source: *4R Plant Nutrition IPNI **Soil Fertility and Fertilizers

35 Potassium

36 Field ID Western Reserve # Penn State S (Back Cow Pasture) Current Soil Test Level #/acre CEC Desirable Range 288 #/acre ppm #/acre 128 ppm ppm #/acre Buildup, Maintenance, or Drawdown? Drawdown Maintenance

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38 Common Fertilizer Materials Material N P K Urea Ammonium sulfate Diammonium phosphate Monoammonium phosphate Triple superphosphate Muriate of potash Sulfate of potash