1. Soil Sampling Topic # 2036 Mr. Christensen

2. A little Review O Horizon (Organic) A Horizon (Topsoil) E Horizon (Subsurface ) B (Subsoil) C (Substratum) R (Bedrock)

3. Michigan State University http://www.geo.msu.edu/geo333/soils.html

4. Soil Map Montcalm County Montcalm County, Michigan Fairplains Sheet 51 Scale 1:20,000 Mm McBride Sandy Loam Ca Carlisle

5. Why Sample Soils? Determine plant nutrient availability Diagnostic tool for problem soils Soils in Michigan vary greatly and change overtime due to crop removal Tests include: pH, electrical conductivity (EC), organic matter, nitrate-nitrogen, phosphorus, potassium and other micronutrients

6. What is pH? pH is a measure of the acidity or alkalinity in the soil. pH is measured by the number of hydrogen ions present in the soil solution The pH scale goes from 0 (acid) to 14 (alkaline) with 7 as neutral

7. What is pH? pH uses a logarithmic scale for the hydrogen ion concentration pH 6.0 is 10-times more acidic than pH 7.0 pH 5.0 is 100-times more acidic than pH 7.0

8. Most Acid Blueberries 4.0-5.1 Oats 5.0-7.0 Corn 5.5-7.5 Alfalfa 6.3-7.8 Cranberries 4.2-5.0 Potatoes 5.2-6.5 Grasses 5.5-7.5 Beans 6.0-7.5 Azalea Magnolia >5.5 Trefoil 5.5-7.0 Sugar Beets 6.0-7.5 Strawberries 5.0-6.5 Wheat 5.5-7.0 Soybeans 6.0-7.0 Least Acid pH Tolerance

9. Why is pH Important? Soil pH influences the availability of nutrients-a pH of 6-7 is generally favorable for plants, however some plants prefer more acid (blueberries, azaleas (4.5-5.2))or alkaline soils (monkshood, Lady fingers) Impacts the type and population of microorganisms (pH 6.6-7.3 is favorable for microbial activity that promotes nitrogen, sulfur and phosphorus availability.)

10. Ohio State University http://hcs.osu.edu/hcs412/sos6.htm Alfalfa at Low pH Poor growth Lack of Symbiotic bacteria For nitrogen fixation

11. Why is pH Important? Mobility of heavy metals increases with acidity and can leach into streams or aquifers Corrosive to steel under high alkalinity or highly acid soils, concrete is corroded at pH 5.5 or lower Impacts soil applied herbicide effectiveness

12. Future Garden http://futuregarden.com/nutrition/pH_availability_chart.gif

13. Why Does pH and Fertility Change? Climate Weather Soil Mineralogy (sulfur in the soils) Breakdown of organic matter Plants remove nutrients Anhydrous ammonia breakdown

14. Crop Nutrient Removal Crop Yield Nutrients removed in harvest bu/ton/acre N P 2 O 5 K 2 O Alfalfa hay 6 ton 270 60 270 Corn, grain 150 bu 135 64 42 Corn, stover 4.5 ton 101 36 144 Soybeans 50 bu 188 44 66 Cucumbers 10 ton 20 12 36 Celery 30 ton 150 60 480 Wheat, grain 60 bu 75 38 23 Wheat, straw 2.5 ton 30 8 53

15. How Do We Control pH? Soil acidity pH can be raised by adding lime materials (calcium oxide CaO)which neutralize the H+ ions and replacing them with calcium (Ca++)/magnesium (Mg ++ ) Types of Limestone—burnt/hydrated (fast reacting), Calcic/Dolomitic (slower but less expensive), by-products (slag, paper mills,wood ash), Shell meal and Marl Lower pH using Aluminum Sulfate or Sulfur

16. University of Minnesota http://www.soils.umn.edu/academics/classes/soil2125/doc/s11chp6.htm

17. Soil Sampling Equipment Colorado State University http://www.colostate.edu/Depts/SoilCrop/extension/Newsletters/2002/Beans/planning.html Soil Probe Soil Borer Bucket Shovel/spade Soil map Specimen Bag/Box

18. Soil Sampling Select/group Areas based on: Soil type Past management/cropping history Topography Field Size 10-15 acres per sample

19. Soil Sampling 20 cores per sample (1lb sample is 1 part in 2 million “acre furrow slice”) Consistent depth (plow depth 8 inches, minimum tillage include sample from the top 2 inches) timing pH, P and K every three years Nitrogen varies greatly, what are your nitrogen credits? A pre-side dress test may be required to determine needs.

20. Soil Sampling Patterns University of Montana http://www.montana.edu/wwwpb/pubs/mt8602.html Zig-Zag Pattern

21. Soil Laboratory Report

22. A. Aerial Photo of 67 acre field B. Management zones C. 2 acre field grids Lime Application Map Based on soil test results in each zone Cooperative Extension Service The University of Georgia http://www.ces.ugs.edu/pubcd/B1208.htm Grid Sampling

23. Linco Equipment Company-http://www.linco.com/atrssu.htm Agro Company http://www.gpsagro.dk/index_uk.htm 12 Satellite accuracy 2 meters 24 Satellite accuracy 10 cm Up to 7,250 samples a acre On the go sampling is being tested

24. Spreading Lime Rolling Red Prairie Kennel http://www.frenchbrittany.hypermart.net/pics14-08

25. Successful Farming http://www.agriculture.com/sfonline/sf/1997/january/precisn/1.html Apply up to 6 tons of lime per year, retest and reapply if necessary the next year Average pH of 6.0 for field Average pH of 6.5 for field

26. Potassium application map Phosphorus application map Kansas State University http://www.oznet.ksu.edu/pr_prcag/sandpivot.shtml

27. CEC Exchange capacity map at 7250 samples/acre Organic soils>Clay>sands Soil Doctor Systems http://www.soildoctor.com/grid.html