Risk Management as influenced by tillage system

Byron Irvine, Brandon

Managing downside risks in production systems

PricePolicyProduction

Managing Policy risks

Market research Lobby effortsChange crops

Managing price risks (limited potential)

Forward sellingDifferent markets

Industrial vs foodNational or regional vs export

Unique traits Vertical integratation

Managing production risks

WeatherSoil moistureTemperature

WeedsInsects

Diseases

What Risk Factors Does Direct Seeding Influence

1. Soil moisture2. Soil temperature3. Timeliness of operations4. Weeds5. Insects6. Diseases7. Fuel/equipment costs

Major Effects in Wetter areas on timeliness of operations and fuel use

Energy use of CT and ZT Systems (MJ ha-1) on Cereal Stubble 12 year study at Indian Head

CT ZTFertilizer 5886 6003

Herbicides 555 779

Machinery Overhead

375 340

Fuel and lubricants

1668 1132

Total input 8434 8254

Alternative Crop Yields Under Zero Tillage

Impact of zero tillage in Flax yields in Morden (Dave McAndrew)

Year ZT Conv

96 1581 1631

97 1362 1266

98 1740 1620

Impact of zero tillage on Soybean yields in Morden (Dave McAndrew)

Year ZT ZT fall burn

Spring Tillage

Fall & Spring tillage

1998 1660 b 2005 a 2165 a 1954 a

1999 2745 b 3306 a 3308 a 3155 a

2000 3216 b 3389 ab 3438a 3453 a

2001 2742 a 2716 a 2888 a 2687 a

Impact of zero tillage on dry bean yields in Morden (Dave McAndrew)

Year Plants/m2 Days to mature

Seed yield kg/ha

Zt 13.3 c 94.7 d 2107 bZT fall burn 15.7 bc 92.5 bc 2241 a

Spring Tillage 16.3 a 90.5 a 2307 a

Fall & Spring tillage

15.1 ab 91.8 b 2218 a

Direct seeding is all about getting a good stand

• There are at least twice as many opinions about the best seeding systems/openers as there are seeding systems.

• The best comment I ever saw on this issue was a display where an airseeder company had the following sign:

• The Prefect Opener– There was no opener in that location

What is the Impact of opener

• Soil type, soil moisture and residue type and amount can all have significant impacts on the effectiveness of various openers

• Chose a design that makes sense for you but do your best to ensure that the unit will work including– Good chopping and spreading of residues– Stubble height appropriate for your opener/seeder design

Impact of stubble on moisture from snow trapping

Impact of tillage on pre-seeding soil moisture at Indian Head peas preceded by winter wheat (cm)

Tillage 0-30 cm 30-60 cm 60-120 cm

Zero tillage 11.7 10.5 20.3

Minimum 11.8 10.9 21.3

Conventional 10.1 9.5 19.7

Impact of tillage on crop yields at Indian Head (Lafond et al CJPS 1992)

Tillage Pea Flax HRS

Zero tillage 1935 1473 1883

Minimum 1973 1501 1895

Conventional 1785 1208 1558

Impact of Stubble height on Evaporation

Daily average wind, air T, incoming solar radiation, evaporation just above the soil surface during seedling stage of crop.

StubbleHeight

Wind(m s-1)

Air Temp

(C)

Rad.(MJ d-1)

Evap.(g H2O h-

1)Tall ShortCult.

0.5c1.3b1.7a

14.113.812.4

17.9b20.1a20.2a

2.34c2.85b3.17a

(SW Cur Cutforth)

Grain yield (kg ha-1) of crops direct seeded into standing stubble of various heights

Stubble SpringWheat

Pulse Canola

Tall (30 cm)

Short (15 cm)

Cultivated

2560a2418b2255c

2008a1858ab1782b

1410a1334b1239c

(Swift Current Cutforth)

Stubble height at Brandon

Canola Pea Wheat

Tall 1578 2805 2460

Short 1628 2707 2533

Cult 1560 2667 2471

Impact of zero tillage on infiltration

Impact of tillage and straw mgt after 9 years on 1 hr water intake mm

Time No Till +Straw

Till + Straw

Till -Straw

After harvest 1988 455 356 191

After tillage 1988 348 326 215

Before seeding 1989 214 196 156

After harvest 1989 477 425 275

(Singh et al CJSS 1996)

Impact of tillage on Infiltration rate Silt Loam cm hr-1

Date Conv Till No Till

June 17 1.02 2.67

July 31 0.65 1.51

Sept 29 0.47 0.89

(Arooz and Arshad CJSS 1996)

Indirect impacts of zero tillage

WEEDS

Crop Management Study Indian HeadWatson Derksen et al

• Zero tillage was weedier in wet springs regardless of fall conditions

• Conventional tillage was weedier when a dry spring was preceded by dry fall conditions

• Minimum tillage was weedier when a dry spring was preceded by a wet fall.

Brandon wild oat management trial(Doug Derksen)

• 5 rotations compared to the standard– SW, canola, SW, Pea

• ZT is single pass with sideband hoe opener• MT is spring tillage with Heavy duty cultivar

and then seed• Seeder 9” row spacing Conservapak

Impact of tillage on yields of pea kg/ha Brandon SW-Can-SW-pea

Year MT ZT

2000 3694 3814(103)

2001 3074 3165(103)

2002 2034 2837(139)

2003 1497 2124(142)

Tillage System and Wild oat Numbers after one Cycle (emergence from beginning of season until June 3)

Rotation MT ZT

SW-Can-SW-Pea 189 156

SW-Can-WW-Pea 271 147

Mil-Can-SW-Pea 692 341

WSil-Can-WSil-Pea 63 18

Wild oats in ZT and CT systems Indian Head

site ZT CV

SCMS seed bank

60 35

SCMS- Pre-spray

62 35

MRTS residual 15 26

ESCS 7 5

Risks Associated with Air and Soil Temperatures and Low Disturbance Direct

Seeding

Tillage and Straw Management on Soil Temperature Relative to Cultivated Brandon

-3

-2

-1

0

1

2

3

4

Tem

p C

SNight SDay TNight TDay

PlantingEmerg1 wk 3 wks6 wks 9 wks

Daily Temperature at emergence with Differring stubble heights relative to Cultivated

-2-1.5

-1-0.5

00.5

11.5

0-4:00

AM

4-8:00

AM8-1

2:00 P

M12

-4:00

PM

4-8:00

PM8-1

2:00 A

M

Tem

p C

TALLSHORT

Tillage Influences on Risks due to Disease

Major Disease risks broadleaf crops

Canola– Damping off– Sclerotinia– Root rot– Blackleg– Club root,

Pea, bean– Scelerotinia– Root rot– ascochyta

Major Disease risks cereals

Wheat– Fusarium– Spetoria– Leaf and stem rust– Root rot (take all and common)

• Barley– Fusarium– Net blotch– Leaf and stem rust– Root rot (common)

Does tillage system alter disease risk?

In general more residue will result in more inoculum but does it matter?– Unless you have a total inversion plowing and

leave it there for 4-6 yrs probably for many diseases not as the current year’s weather is the overriding factor.

– There are some people who believe that tillage can reduce blackleg in canola by burying the residue

Fusarium Rotation Study 2003: Wheat Yield - Zero Till vs Conventional

1000

1200

1400

1600

1800

2000

2200

W-W-W-W C-W-C-W W-C-C-W P-C-F-W Wc-Wc-Wc-Wc

Rotation (00-01-02-03)

Yiel

d (k

g/Ha

)

Zero Till

Conventional Till

Disease and tillage interaction Melfort

• Conventional tillage fall and spring tillage plus harrow packing

• Minimum tillage spring tillage plus harrow packing

• Zero tillage• Rotations

– Canola, wheat, barley, barley– Canola, pea, flax, barley– Canola, barley, wheat, pea

Foliar Disease impacts of tillage practices wheat (Bailey et al CJPS 80:169-175)Tillage system

1994 1995 1996 1997

ZT 5.3 2.6 1.8 10.7

Min 5.1 2.9 1.8 10.6

Conv 5.0 2.5 1.8 10.4

Impact of tillage practices on wheat yields Melfort (Bailey et al CJPS 80:169-175)Tillage system

1994 1995 1996 1997

ZT 3960 4500 5200 5100

Min 3610 4130 5430 4860

Conv 3460 4660 4860 4999

Leaf spot diseases in Southern ManitobaGilbert and Woods Can.J. Plant Sci 81:551-559WEST

Pathogen CONV Conservation tillage

S nordorum blotch

8.8 10.4

S triticti blotch 34.0 16.3**

Spot blotch 9.7 6.7

Tan spot 9.9 18.1**

Residue Management Impacts on Crop Establishment

• One (1) cm of residue=1cm greater seed depth• You must be able to get through standing

residue• Rule of thumb has been that stubble height

equal to distance between openers• Disc openers and guidance systems can make it

possible to plant into tall stubble hence less straw on the soil surface.

Seeding Tool Impacts

Fertilizer Placement in One Pass Direct Seeding Systems

Influence of seeding tool canola plant numbers (Derksen Brandon)

year Conservapak Sweeps1996 128 2331997 61 191998 76 431999 92 682000 91 66

Impact of seeding tool canola seed yield T/ ha (Derksen Brandon)year ConservaPak Sweeps1996 1.86 1.801997 1.28 0.451998 0.95 0.511999 1.03 0.882000 0.94 0.82

Effect seeding depth on B. napus emergence with Sweeps and sidebanding of N (plants/m2)

Sweep sideband

N rate 1.5 cm 4.5 cm 1.5 cm 4.5 cm

40 148 90 200 144

80 139 89 194 153

120 143 84 188 136

( Mahli and Gill 84:719-729)

Effect seeding depth on B. napus emergence with Sweeps and side banding of N (plants/m2)

Sweep sideband

N rate 1.5 cm 4.5 cm 1.5 cm 4.5 cm

40 148 90 200 144

80 139 89 194 153

120 143 84 188 136

( Mahli and Gill CJPS 84:719-729)

Effect seeding depth on B. napus yield with Sweeps and side banding of N (T/ha)

Sweep sideband

N rate 1.5 cm 4.5 cm 1.5 cm 4.5 cm

40 1.86 1.55 1.76 1.96

80 1.95 1.67 2.04 1.95

120 2.13 1.50 2.23 2.01

( Mahli and Gill CJPS 84:719-729)

Risk Factors for Seedling Damage

– High fertilizer rates with low SBU• Increase spread or reduce row spacing to reduce damage

– Urea-based fertilizers– Small-seed crops like flax or canola– Low CEC soils– High pH, carbonated soils– Drying conditions after seeding

Slowing Release or Conversion of Urea Can Reduce Seedling Damage

• Slows accumulation of ammonia and fertilizer salts near seedling

• Allows time for fertilizer to move away from seed• Lower concentration means less risk of damage

Effect of Agrotain and rate of seed-placed urea on barley stand density on two soil types

14

16

18

20

22

24

26

28

0 20 40 60 80 100

N Rate (kg/ha)

Stan

d D

ensi

ty (

plan

t/m

) FSL-NIFSL-UICL-NICL-UI

1994-96

Side-Banded Nitrogen Was Relatively Safe In Wheat

• Slight decrease in stand density with N application but effect was minor

• Slight decrease in yield at highest N rate with urea or UAN in the absence of inhibitor

• Damage would not be expected in wheat in most situations

Side-banded N rate and source on wheat stand

100

110

120

130

140

0 40 80 120 160 200

N Rate (Kg/ha)

Plan

ts p

er s

quar

e m

eter

UANUAN+AgrotainUreaUrea+Agrotain

Clay loam 3 years average

Take Home Messages

• Side-band and mid-row bands are effective placements,– If separation is adequate and seed-bed is good

• Side-banding may have some risks– If the fertilizer is too close to the seed.– 1x1” is sometime too close– Consider row spacing

• N placement near the seed has not been shown to be better than mid-row or random banding. – Banding is important, not the precise location of the bands.

Can Zero tillage limit risk

• It can save time• To reduce risk yields must be equal and

costs not increased• Fertilizer damage must be eliminated.