Soil Testing and Practical Application in Agriculture

1

Emmy Williams MS Agriculture/Soil Science - Cal Poly SLO

Laboratory Manager, Betteravia Farms

The Crops

Spinach

Cabbage

Poquito Beans

– Environmentally Responsible

– To know the Nutrient Levels of the Soil

– Avoid over applying Fertilizer

– Improve Soil Conditions

– Increases the Yield

– It saves the growers money

The Benefits of Testing Your Soils

3

Nutrient Management Program - 1989

• N (NO3-N)

• P (P2O5-P)

• K (K2O)

• Soil Sampling

• pH

• ECe

• pH

• ECe

4

Early to Mid - 1990’s

• 30 % Reduction on Nitrogen Fertilizer usage

• Plant tissue sampling and analysis

• Proficiency Testing Program

– NAPT (North American Proficiency Testing

Program)

– ALP (Agricultural Laboratory Proficiency

Program)

5

Quality Control Samples

6

ALP- Laboratory Workshops and Tours

7

PSNT (Pre side-dress Nitrate Testing) - Quick Test

1994-96

• Cooperating Grower on a Research work with U.C. Davis

(Dr. Tim Hartz)

• Nitrogen testing during the life cycle of the crop (Quick Test)

• 20 ppm NO3-N - no additional fertilizer is needed at this time

• Quick Test is a useful tool for growers to efficiently manage

nitrogen Fertilizer Usage

8

Standard Practices Today: Soil Sample Collection

Sampling Pattern

9

6 - 8” core sample

10

Routine Soil Analysis

• Nitrogen (NO 3-N)

• Phosphorus (P2O5- P)

• Potassium (K+)

• Calcium (Ca++) • Magnesium (Mg++) • Sodium (NA+) • Sulfur (SO4-S)

• pH • ECe (salt concentration) • Cyst Nematodes Extraction

11

Cyst nematodes - on plant roots Clubroot Infection on Brocolli

12

Additional Analysis/Record Keeping/Reporting

• Soil Micronutrients

• Soil Texture

• % Organic Matter

• Well Water Irrigation Suitability

– Other analysis are sent out to a commercial laboratory

Testing for Outside Growers

Record Keeping • Crop Rotation • Fertilizer/Soil Amendment Application

Interpretation of Soil Test Report • Crop Sufficiency guideline

13

After Planting - Quick Test Sample Collection

14

Quick Test Set Up

15

Soil Test Report

Date received: 28-Jun-12

Date reported 2-Jul-12

Plot N P K

pH Ece Ca Mg Na SO4-S

ppm

Prev.

crop

CEC (Cmol/kg)

% % % % %

ppm ppm ppm (dS/m) ppm ppm ppm H K Ca Mg Na

1 18 68 255 7.98 1.67 4705 1151 208 139 34.67 1.9 67.8 27.7 2.6

2 45 78 244 7.86 3.36 4511 835 205 365 31.03 2 72.7 22.4 2.9

3 10 64 288 8.01 1.11 5092 1225 174 167 37.16 2 68.5 27.5 2

Crop

Sufficiency 30 40

100-

160

6.8 -

7.2 < 2 40

Optimum Base

Saturation Ratio 3 - 6

60 -

68

12 -

15 1

16

Pre-plant Fertilizer Recommendation #1

Plot Crop Fert. Rate N

ppm

P

ppm

K

ppm pH

Ece (dS/m)

Ca

ppm

Mg

ppm

Na

ppm

SO4-S

ppm

CEC Cmol/kg

%

K

%

Ca

%

Mg

%

Na

1 mx Le none 10 40 181 7.54 2.71 5809 800 240 443 37.22 1.2 78 17.9 2.8

2 Le 0-0-50 200 21 68 97 7.48 4.1 2065 398 201 57 14.76 1.7 69.9 22.5 5.9

+42

3 mx Le

6-20-20 200 34 36 94 7.5 3.55 6413 279 98 146 35.06 0.7 91.5 6.6 1.2

+12 +9 +16

Crop

Sufficiency 30 40

100-

160 6.8-7.2 < 2 40 3 - 6 60 - 68 12-15 1

Optimum Base Saturation

Ratio

Pre-plant Fertilizer Recommendation #2

Fields are Clubroot infected

Plot Crop lime fertilizer Rate N P K pH Ece Ca Mg Na SO4-S CEC

%

K

%

Ca

%

Mg

%

Na

lbs/Ac ppm ppm ppm (dS/m) ppm ppm ppm ppm cmol/kg

1 br 3 6-20-20 400 4 38 62 7.39 0.79 1316 211 71 65 8.81 1.8 74.7 20 3.5

+17 +33 66

+900 Ca

2 br 3

0-0-50 200 2 67 77 7.65 1.14 1481 202 99 84 9.72 2 76.2 17.3 4.4

+42 +900

Ca

Crop

Sufficiency 30 40

100-

160

6.8 -

7.2 < 2 40

3 -

6 60-68 12-15 1

pH Ca Mg

Optimum Base Saturation

Ratio

> 7.2 2400 240

Rec. for clubroot control 18

Average Nitrogen Fertilizer Applied (lbs/ac) Changing Trend - over 17 year

320 331

247 256

204 204

182 172

215

175

150

100

173

109

181

160

120

0

50

100

150

200

250

300

350

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

N Applied lbs/acre

Lb/A

c

19

N-P-K Fertilizer Application On Organic Fields

• N-P-K at Pre- plant

• N-K at bed shaping

• N-P-K with side dress – Quick Test Sample Collection

• N-K through drip irrigation if needed

(Lbs/ Acre)

Crop N P K

Broccolli 169 68 34

Cauliflower 221 68 44

Celery 196 66 42

Lettuce 140 58 34

Average 182 65 39

20

102

85

104

72

84

50

116

87

69

95

68 64

93

59

51

64

92

65 68

53

79

49

69

57

51 47

80

72

55

66 67

0

20

40

60

80

100

120

140

PP

M-

P

PPM- P

Soil Phosphorus Concentration (ppm) - on Selected Field

With no Phosphorus Application in 12 Years.

21

50

Soil Phosphorus Concentration (ppm) - on Selected Field

(2000 - 2013)

22

46

43

70 68

60

51

57

42

53

56

42

32

41 42

34

56

38

35

27

30

43

35

27

34 35

56

33 35 35

40

33

0

10

20

30

40

50

60

70

80

P -Fertilizer Applied

PP

M-P

91% 91%

79% 79%76%

53%

37%

50%50%

38%

46%

10% 10%

2% 2%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Acres fertilized (%)

1992 20091993 1998 2008200720061994 200520001999 2004200320022001

% P

- A

pp

lica

tio

n

23

The Changing Trend of Phosphorus Fertilizer Application

Drip Irrigation Regulates the Output of Water and Fertilizer

24

Using Soil Texture to Determine Pre-Irrigation Time

25

Sand Clay Silt Texture FC (in water /ft of

soil)

W.P. (in water /ft of

soil) A.W.

FC- WP

34.6 17.8 47.6 Loam

17.8% 3.19581882 1.3933 1.8024494

1.80244

in/ft soil

Average sprinkler output 0.2"/Hr. To Irrigate to output 1.802 in/ft soil will

take : 1.8”/0.2” = 9 hours

(http://staffweb.wilkes.edu/brian.oram/soilwatr.htm)

Practices to contain Discharge Water

Barriers in the Ditches to slow down water Flow

26

27

Soil Testing Reduces:

• Fertilizer Usage

• Environmental Impact

• Production Cost

Emmy@bonipak.com

28

Pre-plant Fertilizer Recommendation #1

Plot Crop lime Fert. Rate N

ppm

P

ppm

K

ppm pH

Ece (dS/m)

Ca

ppm

Mg

ppm

Na

ppm

SO4-S

ppm

CEC % % % %

Cmol/kg K Ca Mg Na

1 ca no 13 87 202 7.72 0.95 5026 731 142 105 32.36 1.6 77.7 18.8 1.9

2 br no 5 68 181 7.57 2.46 4559 831 149 767 30.83 1.5 73.9 22.5 2.1

3 br no 4 65 181 7.59 3.08 4347 821 232 700 30.05 1.5 72.3 22.8 3.4

4 br no 4 40 167 7.81 3.54 3584 708 215 304 25.18 1.7 71.2 23.4 3.7

5 mx Le no 7 54 126 7.44 2.22 2320 471 190 120 16.02 1.6 70.1 24.2 4

6 mx Le no 16 57 130 7.57 1.76 2819 689 198 183 21.03 1.6 67 27.3 4.1

7 mx Le no 10 40 181 7.54 2.71 5809 800 240 443 37.22 1.2 78 17.9 2.8

8 Le 0-0-50 200 21 68 97 7.48 4.1 2065 398 201 57 14.76 1.7 69.9 22.5 5.9

+42

9 mx Le 6-20-20 200 34 36 94 7.5 3.55 6413 279 98 146 35.06 0.7 91.5 6.6 1.2

+9 +16

Crop

Sufficiency 30 40

100-

160 6.8-7.2 < 2 40 3 - 6 60 - 68 12-15 1

Optimum Base Saturation

Ratio

Plot Crop Fertilizer Rate N ppm K pH Ece Ca Mg Na SO4-S CEC %K %Ca %Mg %Na

ppm ppm ppm (dS/m) ppm ppm ppm ppm cmol/kg

1 Ce 0-0-50 300 1 62 86 7.55 1.3 1741 318 99 109 12.01 1.8 72.5 22.1 3.6

+60

2 le 6-20-20 300 32 38 102 7.44 2.64 2251 506 205 201 16.62 1.6 67.7 25.4 5.4

12 9 +16

3 le 0-0-50 200 23 48 94 7.42 2.45 1951 388 168 147 13.96 1.7 69.9 23.2 5.2

+42

4 le no 7 54 187 7.63 1.97 3080 670 208 150 22.37 2.1 68.9 25 4

5 le no 14 53 148 7.68 1.65 3053 663 132 201 21.74 1.7 70.2 25.4 2.6

6 mix

Le no 11 51 149 7.83 1.7 5825 779 216 102 36.94 1 78.8 17.6 2.5

7 mix Le no 12 50 105 7.56 1.53 1832 354 93 57 12.78 2.1 71.7 23.1 3.2

8 mix Le no 16 67 223 7.12 1.81 3782 896 269 190 28.12 2 67.3 26.6 4.2

9 Ro no 30 79 220 7.8 2.33 3465 609 251 154 24.06 2.3 72 21.1 4.5

10 Ro no 24 48 157 7.8 1.76 3401 481 172 230 22.16 1.8 76.7 18.1 3.4

Crop Sufficiency 30 40

100-

160 6.8-7.2 < 2 40 3 - 6 60-68 12-15 1

Optimum Base Saturation Ratio

Pre-plant Fertilizer Recommendation #2

30

Pre-plant Fertilizer Recommendation #3

Plot Crop lime Gyp fertilizer Rate N p K pH Ece Ca Mg Na

SO4-

S CEC %K %Ca %Mg %Na

lbs/Ac ppm ppm ppm (dS/m) ppm ppm ppm ppm cmol/kg

1 br 2 6-20-20 400 4 38 62 7.39 0.79 1316 211 71 65 8.81 1.8 74.7 20 3.5

+17 +33

2 br 2 6-20-20 400 4 37 55 7.36 0.71 1279 219 71 55 8.67 1.6 73.8 21.1 3.6

3 br 2

0-0-50 200 2 67 77 7.65 1.14 1481 202 99 84 9.72 2 76.2 17.3 4.4

+42

4 br 0 20 38 169 7.67 2.02 5385 708 119 114 33.78 1.3 79.7 17.5 1.5

5 ca 0 8 68 123 7.39 0.84 2484 496 108 51 17.34 1.8 71.6 23.8 2.7

6 br 0 16 50 237 7.2 2.64 6395 849 140 223 40.27 1.5 79.4 17.6 1.5

7 ca 0 3 50 139 7.41 1.34 3482 592 123 300 23.23 1.5 74.9 21.2 2.3

Crop

Sufficiency 30 40

100-

160

6.8 -

7.2 < 2 40 3 - 6 60-68 12-15 1

pH Ca Mg

Optimum Base Saturation

Ratio

> 7.2 2400 240

Rec. for clubroot control 31

Calcium to Magnesium Ratio (3 year Field History)

Date N P K pH

Ece Ca Mg Na SO4-S

CEC %K % Ca % Mg %Na

ppm ppm ppm (ds/m) ppm ppm ppm Cmol/kg

8/20/2009 8 40 200 6.95 0.86 2209 1283 234 27 23.27 2.2 47.2 45.7 4.4

3/24/2010 19 67 300 7.41 0.78 2930 1687 258 15 30.6 2.5 47.9 45.9 3.7

4/19/2010 12 58 478 7.14 0.84 3826 2218 257 10 39.96 3.1 47.9 46.3 2.8

8/18/2010 8 50 252 7.22 0.93 3076 1736 329 25 31.92 2 48.2 45.3 4.5

4/12/2011 6 46 398 7.3 0.69 3190 2013 328 74 35.17 2.9 45.3 47.7 4.1

11/1/2011 31 50 251 7.16 1.13 3064 1774 193 33 31.59 2 48.5 46.8 2.7

5/24/2012 6 62 365 7.02 0.84 2616 1631 193 26 28.45 3.3 46 47.8 2.9

11/26/2012 34 46 306 7.25 1.46 3094 1775 346 24 32.55 2.4 47.5 45.4 4.6

Crop

Sufficiency 30 40 100-160 6.8-7.2 < 2 40 3 - 6 60 - 68 12 - 15 1

Optimum Base Saturation Ratio 32

Calcium to Magnesium Ratio (3 year Field History)

Date Ca Mg CEC

%K % Ca % Mg %Na ppm ppm Cmol/kg

8/20/2009 2209 1283 23.27 2.2 47.2 45.7 4.4

3/24/2010 2930 1687 30.6 2.5 47.9 45.9 3.7

4/19/2010 3826 2218 39.96 3.1 47.9 46.3 2.8

8/18/2010 3076 1736 31.92 2 48.2 45.3 4.5

4/12/2011 3190 2013 35.17 2.9 45.3 47.7 4.1

11/1/2011 3064 1774 31.59 2 48.5 46.8 2.7

5/24/2012 2616 1631 28.45 3.3 46 47.8 2.9

11/26/2012 3094 1775 32.55 2.4 47.5 45.4 4.6

3 - 6 60 - 68 12 - 15 1

Optimum Base Saturation Ratio 33

Evaluation of Phosphorus (ppm) - on 20 Selected Fields

5 Year Average

34

75

52

41 34

26

47 48 45

79 83

68

60

35

53

64

45

97

41

52

113

0

20

40

60

80

100

120

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Av

era

ge

P (

pp

m) 5

0 pp

m