Biosolids Nutrien Management an Soil Testing. Craig Cogger, Soil Scientis WSU Puyallup

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1 Biosolids Nutrien Management an Soil Testing Craig Cogger, Soil Scientis WSU Puyallup

2 Nutrient Manageme Meet crop nutrient needs Maintain soil quality Conserve resources Protect water quality -- reduc leaching and runoff risk

3 Plant Nutrients Major Nutrients Nitrogen Phosphorus Potassium Calcium Magnesium Sulfur Micronutrients Boron Iron Manganese Zinc Copper Chloride Molybdenum

4 Plant Nutrients Major Nutrients Nitrogen Phosphorus Potassium Calcium Magnesium Sulfur Micronutrients Boron Iron Manganese Zinc Copper Chloride Molybdenum

5 What do nutrients do Example: Nitrogen Chlorophyll - photosynthesis Amino acids and proteins Amino Acid DNA Plant and Soil Sciences, U Nebraska Bern Kohler, Ohio State Univ.

6 Nutrient Deficiencies Reduce plant growth, health, and yield. Nutrient deficiencies can sometimes be identified by observing symptoms. P deficiency in cor Mg deficiency in cor

7 Problems with excess nutrients Nitrogen:!Plant health, fruit yield and qualit!groundwater quality Boron:!Toxicity

8 How do nutrients become available to plants?

9 Mineral Matter Organic Matter K Ca Mg Not available N S P Weathering K + Ca ++ NH + 4 SO -2 4 soluble, available Biological relea What happens to these nutrients when it rains?

10 K Ca Mg Not available N S P K + NH 4 + Ca +2 SO 4-2 soluble, available clay OM

11 K Ca Mg Not available N S P Ca ++ K clay K + NH + 4 Ca +2 SO -2 4 soluble, available K + - Mg OM

12 Cation Exchange Capacity Cation (+ ion) Anion (- ion) Cation exchange capacity (CEC): Negative sites on clay and organic matter that can hold cations.

13 Anion Binding Anion exchange capacity is very low most soils. Some anions (such as phosphate) ar bound by penetration into surface o mineral. Fe Fe OH OH + H 2 PO 4 - Fe Fe O O P O OH + O + H

14 Nutrient Anion Availability Anion Binding Solubility PO -3 4 strong low SO -2 4 v. weak high NO - 3 v. weak v. high

15 Nitrogen Cycle Organic N Ammonium NH 4 + Nitrate NO 3 - Soil organic matt Plant residues, Manure Plants, Microbes N fixat Leaching Gases (N 2, N 2 0) Atmosphere

16 Comparing organic and processe fertilizers Organic Little or no processing Low analysis Usually slow release Often unknown analysis Usually a source of OM Processed Industrial process High analysis Usually fast relea Known analysis No OM

17 Nutrient uptake The forms of nutrients taken up by plants are the same -- whether the source of the nutrients is the soil, organic fertilizer, or a manufacture fertilizer.

18 The soil ecosystem Residue decomposition Nutrient cycling Aggregation and porosity Enhance plant growth Break down many contaminants

19 Long-term biosolids dry product application to tall fescue ( ) Long term biosolids dry product application to tall fescue Soil C and N, 0 to 6 inch depth Summer 2008, 6 years after final biosolids application Total N 3.0 Total N Total N=0.01 bs app+.15, r 2 = Total C (%) Total C=0.12 bs app+1.9, r Total C Total C 2 = Total N, %, 0-6" Annual biosolids application rate, dry tons/acre 0.12

20 Biosolids and oth nutrients These nutrients accumulate in the soil w biosolids are applied to meet N needs: Phosphorus Zinc This nutrient will decline in soil if biosoli are the sole source of nutrients: Potassium

21 Soil ph Indicates relative acidity or alkalinity ph 7 = neutral; less than 7 = acid; more than 7 = alkaline or basic Logarithmic scale Adapted from library.thinkquest.

22 Why is ph importan Nutrient availability Availability of toxic metals Microbiological activity

23 What affects ph? Climate Humid areas tend to have acid soils, and arid areas tend to have alkaline soils. Parent material Some parent materials contain lime and keep ph higher. Management Many fertilizers tend to produce acidity.

24 Desirable ph Ranges Most row crops 6 to 7.5 Turfgrass and pastures 5.5 to 7. Acid loving plants 4.5 to 5.

25 Increasing ph Lime (CaCO3) neutralizes acidity Lime supplies Ca, which is often deficien in acid soils Dolomite lime also supplies Mg Apply lime based on soil test, and lime o those crops that need it.

26 Soil Testing

27 Soil testing Theory: Extracts plant-available nutrien Results: Used to predict nutrient availabi and need. Biosolids management: Indicates which biosolids nutrients are needed. Identifies excessive nutrient levels in soil.

28 Soil test vs. crop respons Calibration of Bray P1 soil test for winter wheat in western Oregon 30 field sites, Roberts et al., Fertilizer Experiments with Winter Wheat in Wester OSU Ag Expt Sta Tech Bull 121

29 Soil testing requirements Vary, depending upon your permit Most soil testing is voluntary; mu of it is useful for biosolids management.

30 Types of tests Pre-application tests: nutrients, metals, (nitrate east of Cascades Post-harvest nitrate: a check on application rates. Nutrients: Check on nutrient sufficiency, biosolids benefits.

31 Basic Soil Nutrient Tes Standard agricultural test: (P K, Ca, Mg, B, ph, lime requirement)

32 When to sample? It is best to be consistent from year to year. Nitrate tests are taken at specif times. Standard tests can be taken at a time before fertilization.

33 How often to sample Sample each unit every 1 to 3 years or at least once per cro rotation.

34 How to collect a so sample: Area: A field, portion of a field, or several sm fields with similar soils and management history.

35 Taking a Sample Take cores in a zig-zag pattern across field Avoid unusual areas Air-dry and mix well Subsample mixture and fill sample bag

36 Sampling tools Use tools that collect uniform core Hydraulic Probe Hand Probe

37 How deep to sample Nutrients, typically 12 inches. Nitrate 12 inches, except for dryland grain production, where entire root zone is sampled.

38 Sample handling Keep moist samples cool during and after sampling. Refrigerate, freeze, or bring direc to lab. OR, spread in thin layer and air dry Send about 1 pint to lab, carefully labeled.

39 Choosing a lab Does the lab routinely do agricultural tests? Do they use OSU or WSU test method Do they give fertilizer recommendation What information do they need? How to send sample? Cost? Turn-around time? What does report look like?

40 Choosing a lab Quality assurance: Does lab participate in proficiency testin program or sample exchange? Quality assurance: Submit a known sample for a check.

41 Soil nitrate tests Pre-sidedress nitrate test 1. Mid-season nitrate test to determin need for additional N. 2. Calibrated for corn. 3. Research on other crops in progress Post-harvest nitrate test 1. Is excess leachable N in soil at end season? 2. Use to modify next year s N management.

42 Soil nitrate tests PSNT - taken when corn is 6-12 inches tall, or similar growth stage for other crops! Sample 0-12 inch depth. Post harvest test- September 1 to October 15.! Sample 0-12 inch depth.! Sample preservation is important Reference: EM8650. The pre-sidedress nitrate test

43 Interpreting soil tes Nutrient status Low, medium, high Fertilizer recommendation Reference: EC Soil Test Interpretation Guide

44 Soil sampling an interpretation info Click on SOILS and SOIL TESTING button for information on soil sampli soil testing labs, and soil test interpretation.