Trends in Soil Management for Turf. David C. Smith P.Ag DCS Agronomic Services

Transcription

1 Trends in Soil Management for Turf David C. Smith P.Ag DCS Agronomic Services

2 Points for Today s Discussion Soil Testing Considerations Soil test interpretation How water moves in the soil Recommendations for Turf

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4 The Only Thing That Never Changes is Things Keep Changing

5 OMAFRA Publication 611 Soil Fertility Handbook Turfgrass Soil Fertility and Chemical Problems Carrow, Waddington & Rieke

6 Golf Course Management - Research Clarifying Soil Testing 1 Sept Clarifying Soil Testing 2 Jan Clarifying Soil Testing 3 Jan By: R.N. Carrow, L. Stowell, W. Gelernter, S. Davis, R.R. Duncan and J. Skorulski

7 PACE Turf Owned and managed by: Larry Stowell Ph.D. and Wendy Gelernter Ph.D.

8 Balance What is a balanced soil?

9 Soil Balance Chemical Fertilizers, Lime Pesticides,pH CEC Cations Anions Physical Texture, Structure Compaction, Hardpan Porosity Biological Bacteria, Fungi, Algae Actinomycetes Protozoa, Earthworms

10 Soil Components ORGANIC MATTER (5%) WATER (25%) MINERAL (45%) AIR (25%)

11 Mineral Uptake Mass Flow

12 Air and Gas Exchange Most abundant elements in plants Not applied as fertilizer Carbon (45%) Hydrogen (6%) Oxygen (45%)

13 Differences in Mobility of Mineral Nutrients in the Phloem Nutrient High Mobility Intermediate Mobility Low Mobility Calcium X Manganese X Iron X Silicon X Copper Zinc Boron Sulfur X X X X Molybdenum X Chlorine amino-h Sodium Nitrogen Phosphorus Potassium Magnesium X X X X X X X Data from Pages of Turfgrass Soil Fertility and Chemical Problems

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16 Soil Sampling Critical to development of successful nutritional, irrigation and soil management program Soil / Plant / Thatch Inspection?

17 Soil Sampling for submission to lab Number of samples (probes) Boundaries of sampling areas Depth of samples Time of sampling

18 Soil Testing at the Lab Why so confusing? No defined system of analysis or reporting of data due to different labs specializing in different soil location and various crops

19 ph Measurement of hydrogen ion activity or concentration in soil Generally done as a paste extract at a soil to ionized water ratio of 1:1 Influence on nutrient availability

20 ph

21 Buffer ph Determines the ability of a soil to resist change in ph Measured by adding buffer solution to soil and reading ph after one hour. Used to determine need for lime Charts available for making lime calculations

22 Soil testing Saturated Paste Extract (SPE) Nutritional Soil Audits (NSA) using chemical extractants to provide an estimate of nutrition available to plants over a defined period of time

23 Testing - Saturated Paste Extract (SPE) Developed by US Salinity Lab in 1954 to determine: Electrical Conductivity (ECe), Sodium Adsorption Ratio (SAR) Boron toxicity

24 Saturated Paste Extract Guidelines Saturated Paste Extract Guidelines Parameter Function Ideal ECe Measure of Soluble Salts <4 DS/M SAR Determine Na within or applied to soil and identify potential for problems <3 Calculation Boron Measure for potential Boron toxicity <2 ppm

25 Testing - Saturated Paste Extract (SPE) Compost sources may contain toxic levels of boron or salt content important to check before using for landscape plantings

26 Testing Nutritional Audit & Inventory Report Base Cation Saturation Ratio (BCSR) Conventional Sufficiency Level of Available Nutrients (SLAN) Minimum Levels for Sustainable Nutrition (MLSN)

27 Testing Nutritional Audit & Inventory Report Base Cation Saturation Ratio (BCSR) Determines percentage of cation saturation levels. Ca, Mg, K, Na & H. Requires accurate determination of the soils nutrient holding capacity for positively charged cations

28 Testing Nutritional Audit & Inventory Report Sufficiency Level of Available Nutrients (SLAN) and (MLSN) (SLAN) and (MLSN) systems developed to estimate quantity of plant available nutrition in the soil SLAN and BCSR if used correctly should compliment each other

29 Inductively Coupled Plasma Analyzer (ICP)

30 Extractants Approximately 1% of soils inventory of minerals are plant available Water first and simplest extractant - (SPE) More robust chemicals (extractants) required to determine soils nutrient inventory status Soil Audit and Inventory Report.

31 Extractant Options Nutrient Phosphorous Potassium Soil Medium Sufficiency Range (ppm) Medium Sufficiency Range lbs./a (P2O5) Extractant Nutrient Soil Medium Sufficiency Range ppm Medium Sufficiency Range lbs./a Extractant all 15 to to 137 Mehlich I all 200 to to 700 Mehlich I all 26 to to 247 Mehlich III (ph 2.5) all 500 to to 1500 Mehlich III (ph 2.5) Calcium all 15 to to 137 Bray 1 all 500 to to 1500 NH 4 OA c (ph 8.1) all 51 to to 362 Bray 2 all 500 to to 1500 Morgan all 12 to to 128 Olsen all 10 to to 91 Morgan Sulphur all 10 to to 40 Ca(H 2 PO 4 ) 2 all 30 to to 120 NH 4 OA c (ph 8.1) sands 75 to to 350 NH 4 OA c (ph 8.1) all 15 to to 80 Mehlich III others 100 to to 470 NH 4 OA c (ph 8.1) sands 50 to to 232 Mehlich III (ph 2.5) sands 30 to to 120 Mehlich I others 75 to to 352 Mehlich III (ph 2.5) others 50 to to 200 Mehlich I sands 50 to to 200 Mehlich I sands 60 to to 240 Mehlich III (ph 2.5) others 90 to to 400 Mehlich I Magnesium others 70 to to 280 Mehlich III (ph 2.5) all 155 to to 624 Olsen sands 100 to to 400 NH 4 OA c (ph 8.1) all 120 to to 348 Morgan others 140 to to 500 NH 4 OA c (ph 8.1) all > 100 > 200 Morgan

32 ph - influence

33 Extractants - Chemical Weak acids (acidic, citric, lactic,) and stronger acids (hydrochloric, sulphuric, nitric) Often two or more acids used together to extract multiple minerals

34 Extractants Mehlich III (ph 2.5) Developed by Dr. Adolph Mehlich to serve as a universal extractant for all soils Multi-element extracting solution composed of Acetic Acid, Ammonium Fluoride, Ammonium Nitrate and the chelating agent - Ethylene Diamine Tetraacetic Acid (EDTA) Considered dependable to ph of 7.3 Routinely used in Quebec and Maritimes

35 Extractants - Bray 1 Represents plant available P Designed for determining P requirements in acid soils Not recommended for alkaline soils with ph above 7

36 Extractants - Bray 2 Bray 2 phosphorus represents phosphorus considered plant available and about 10-15% of the unavailable -P. Not a lot of good calibration data is available. Designed for determining P requirements in acid soils Not recommended for alkaline soils with ph above 7

37 Sodium Bicarbonate (Olsen) Alkaline soils (ph 7.5) can affect the P extraction process in Mehlich III.-P and Bray II-P tests. Olsen-P test designed for high ph soils. Request Olsen-P test if the soil is alkaline

38 Extractants - Ammonium Acetate ph 8.1 Developed for extracting Mg, Ca, S and K, Well suited for use on alkaline soils ph >7

39 Extractants - DTPA Diethlylene Triamine Penta-acitic Acid (DTPA) Component of Mehlich III extractant Used alone for extraction of minor elements

40 Phosphorous Most complex in terms of soil chemistry Tends to balance nitrogen, hastens plant maturity, improves quality of fruit (Seed) and disease resistance Important that extractant match soil submitted for analysis - acid soil vs. calcareous soil

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43 Potassium Important nutrient required for growth and stress tolerance Ongoing research to evaluate potassium requirements for turf Mehlich III and Ammonium Acetate two popular extractants for potassium determination

44 Calcium Required as a catalyst for many plant functions Values may be low in low CEC soils resulting in a need for limestone applications Mehlich III and Ammonium Acetate two popular extractants for calcium determination

45 Magnesium Part of chlorophyll molecule Important for photosynthesis and thus important factor in overall plant health enters in formation of proteins in plants and related to movement of carbohydrates from leaves to stems Mehlich III most popular extractant

46 Sulphur Important constituent for plant growth Functions in formation of proteins Number of extractants can be used for sulphur extraction Ammonium Acetate, Mehlich III and Calcium Dihydrogen Phosphate Ca(H 2 P04) 2

47 Minimum Levels for Sustainable Why MLSN? Nutrition (MLSN) Measurement sustainability Reduction in amount of fertilizer and inputs required for application of fertilizer Reduced environmental risk Global Soil Survey - ongoing

48 Soil Test Guidelines Conventional & (MLSN) Nutrient Analytical Test Conventional ppm (MLSN) ppm Phosphorous Olsen >12 >6 Phosphorous Bray 2 >75 >25 Phosphorous Mehlich 3 >50 >18 Potassium Mehlich 3 >110 >35 Calcium Mehlich 3 >750 >360 Magnesium Mehlich 3 >140 >54 Sulphur Mehlich >13 Nitrate N KCL Ammonium N KCL <7 0-7 Total N KCL <

49 Micronutrients - ph Due to influence of ph on availability of minor elements values should not be considered absolute. Solubility index values for manganese, iron and zinc can be calculated from soil test data. Comparing plant tissue analysis values with soil test and solubility index values helps round out and validate the need for minor elements.

50 Micronutrients * In high ph soil - no good soil test for Iron Low side of CL High side of CL Low ph Low CEC High ph High CEC Consider impact of Mass Flow!

51 Micronutrient Micronutrient Method Critical Soil Level Range Boron Mehlich III 0.4 to 1.5 Hot Water 0.3 to 2.0 Iron * Mehlich III 50 to? DTPA 2.5 to 5.0 Manganese DTPA 2.0 to 5.0 Mehlich III 10 to 35 Copper DTPA 0.2 to 2.5 Mehlich III 0.6 to 3.0 Zinc Mehlich III 1.0 to 4.0 DTPA 0.3 to 2.0 Molybdenum Hot Water 0.1 to 0.25 > 8 may be toxic

52 Suggested Reading OMAFRA Publication 611 Soil Fertility Handbook Turfgrass Soil Fertility and Chemical Problems Carrow, Waddington & Rieke

53 Suggested Reading Golf Course Management - Research Clarifying Soil Testing 1 Sept Clarifying Soil Testing 2 Jan Clarifying Soil Testing 3 Jan By: R.N. Carrow, L. Stowell, W. Gelernter, S. Davis, R.R. Duncan and J. Skorulski

54 Thank You David C. Smith P.Ag, CGCS DCS Agronomic Services