all you ever really needed to know about yield potential...

ALL YOU EVER REALLY NEEDED TO

KNOW ABOUT YIELD POTENTIAL,

SALINITY AND SOIL PROPERTIES

IS IN THE LANDSCAPE.

OR NOT.

Curtis Cavers (AAFC) and Marla Riekman (MAFRD)

Purpose

To link soil-landscape-productivity concepts to

soil management issues

Audience participation is required!

Use the iclickers to answer questions based on:

General soil/agronomy principles

Soil properties and landscape processes

Linking properties and processes to productivity

General Soil/Agronomy Principles

What is the typical rooting depth of canola?

A. 6 inches (15 cm)

B. 1 foot (30 cm)

C. 2 feet (60 cm)

D. 4 feet (120 cm)


Answer: D - 4 feet (120 cm)

Canola root depth will vary from 36 to 76

inches (90 to 190cm)

Average about 56 inches (140cm) at maturity

for B. napus


Tillage tends to ________ water flow through

root channels and macropores.

A. increase

B. decrease


Answer: B - Decrease

Zero Tillage Conventional Tillage

Photos: CSIRO


Which cereal crop is most sensitive to excess

moisture?

A. wheat

B. barley

C. oats

D. corn


Answer: B - Barley

Barley is highly sensitive to ethylene (C2H4)

toxicity

Ethylene accumulates around plant roots during

excess moisture conditions

Barley will experience root death at very low C2H4

concentrations

Soil Properties & Landscape Processes

Using the catena (landscape cross-section)

below, which of the four landscape positions is

most likely to have the thinnest A horizon?

A

B

C D

.

4504003503002502001501005000

100

200

300

400

Parent Material

Th ick ness of B

Th ick ness of A

Dis tance (m)

Rel

ativ

e E

lev

atio

n a

nd

Th

ick

nes

s (c

m)


Answer: A - Knoll

A. Moulin et al. 1994. Can. J of Soil Sci.



most likely to have a soil profile with a typical

A/B/C horizon sequence?

A

B

C D


Will insert soil horizon sequence diagram...

Soil properties & landscape processes Answer: B - Midslope



most likely to have the highest (shallowest)

water table?

A

B

C D


Answer: D - Depression


below, which of the four landscape positions

would you expect corn and soybean yields to

be the lowest if salinity is present?

A

B

C D


Answer: C – toe slope

Les Henry, MAC Proceedings, 2012

In order to manage salinity, what is the most

crucial landscape position to address through

enhanced water management practices?

A. B

B. C

C. D

D. all positions (i.e. the entire field)

A

B

C D

Linking Properties & Processes to Productivity

Answer: D - All of the

landscape positions




most likely to have the most stable crop yields?

A

B

C D

Answer: B – Midslope; however this

can vary from field to field

A. Moulin, 2012. ASI Project Report

Yield loss due to soil erosion at position A is

best addressed in the short term by:

A. Manure applications

B. Extra fertilizer application

C. Irrigation

D. Tile drainage

A

B

C D



22 22 22 22

22

22 2222

1815

12 10

0

5

10

15

20

25

Yie

ld b

u/a

c

None 2" 4" 8"

No fert

1X fert

2X fert

Soil removed

No fert

1X fert

2X fert

22

22 222222

Answer: B – Extra Fertilizer Application

Wheat Yield – Pembina Clay Loam

3330 29 28

32

28

21

1032

26

138

0

5

10

15

20

25

30

35

Yie

ld b

u/a

c

None 2" 4" 8"

No fert

1X fert

2X fert

Soil removed

No fert

1X fert

2X fert

32

33

28 2928

30

However, this is soil texture dependent

Wheat Yield – Rheinland Loamy Fine Sand


Using the practice of landscape restoration at

Position A, by how much could crop yield

productivity be increased?

A. 10%

B. 20%

C. 40%

D. 60% and higher

A

B

C D


0

10

20

30

40

50

60

peas wheat flax

Yie

ld b

u/a

c

knoll

restored

depression

scrapped

eroded knoll

restored

depression

scraped

Answer: D – 60% and higher


64%

133%

94%

Diane Smith, MSc Thesis, 2008

• 4” of topsoil

taken from

depression and

spread on eroded

knoll

Where is seedling toxicity due to seed-placed

fertilizer most likely to express itself?

A

B

C D


Depression Soil Hilltop Soil

Nesbitt site - MAP/AS blends

0

50

100

150

200

250

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

Pla

nts

m⁻²

Days after Emergence

Control

Low MAP/Low AS

Low MAP/High AS

High MAP/Low AS

High MAP/High AS 0

50

100

150

200

250

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

Pla

nts

m⁻²

Days after Emergence

Answer: A - Knoll

Nesbitt Site - Depression Soil Nesbitt Site - Hilltop Soil

Laryssa Grenkow M.Sc. Thesis, 2013

Soil Characteristics

Minnedosa Nesbitt

Soil Characteristic Depression Hilltop Depression Hilltop

Soil Series Erickson Erickson Hilton Hilton

Texture SCL CL SL L

pH 7.2 7.8 7.7 7.9

OM (%) 9.0 3.2 6.0 1.8

CEC (meq) 29.7 32 26.3 28.2

Calcium Carbonate (%) 0.4 8.4 0.5 21.0

Container Capacity (%)z 39.8 33.1 25.8 17.2

z Gravimetric water content

Laryssa Grenkow M.Sc. Thesis, 2013

Where should practices to mitigate or prevent

soil compaction be conducted?

A. C

B. D

C. Headlands, if evidence

of compaction is present or

conditions favourable for compaction to occur

D. The entire field

A

B

C D


Answer: C - Headlands, if evidence of

compaction is present of conditions favourable

for compaction occur

However, the depressions may be at risk of

compaction depending on moisture conditions.


Summary

Know your agronomic principles

Soil Principles:

Water is the main driver

Elevation is a clue

Crop yield is a report card on soil productivity

4 long-term yield robbers (soil quality):

Erosion

Salinity

Compaction

Organic matter depletion

Thank you for your participation!

all you ever really needed to know about yield potential...

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