IWM

Diverse cropping systems (in space

and time)

Cultivar choice &

establishment

Field/soil managem

ent

Targeted control

Monitoring &

evaluation

Integrated Weed Management,

experiences from the Netherlands

Uppsala February 2019 Marleen Riemens et al.

Content

Big trends and the impact on primary production

Context: Towards AgroEcology & Technology

Integrated Weed Management:

● Diversified cropping systems

● Cultivar choice: cover crops

● Tillage and field management

● Mechanical weed management & robotics

● Monitoring

Big trends & Agriculture

Food Safety Water

QualityPublic opinion and

legislation

Climate

Change

Ecology

and

Biodiversity

3

Our Research partners (both public and private) develop their vision, strategy and R&D policy to solve/address these issues.

The Netherlands 2nd

September 2017

Oktober 2017

Continue on current path or sustainable innovation?

Transition to IWMContinuation

More, more, more

New modes of action

Same system?

A systems approach

IWM

Diverse cropping systems (in space

and time)

Cultivar choice &

Establish-ment

Field/soil managem

ent

Targeted control

Monito-ring &

evaluation

Challenges & Solutions

1 problem, 1 solution system approach

Reactive pro-active: prevention

Biodiversity poor biodiversity rich

Ecology meets technology meets agronomy

6

Agro ecology with high tech support

7

Integrated Weed Management (IWM)

focuses on the management of weed populations, extending the current growing system :

● Reduction of seed rain;

● Prevent establishment of weed seedlings;

● Prevent seedlings to mature.

8

IWMPRAISE

EU grant agreement Nº 727321

Mature plants

Reduce the impact of weeds on the crop

2

Prevent the establishment

of weeds

Reduce seed return

TransplantingSowing dateSeed rateCultivar choiceSpatial arrangementPost-emergence herbicidesMechanical weedingIntercroppingPatch/band sprayingBiological controlSowing depthNutrient placementSeed vigour

Clean machineryStubble managementWeed seed collection

& destructionpost-emergence herbicidesCrop destruction with herbicidesHand weedingSeed predationMowingFlamingGrazing

Stale seedbedsTiming and depth of cultivationCover cropsPre-sowing herbicidesPre-emergence herbicidesAllelopathic compoundsFlamingMulching (dead and living)Field margin managementClean seed

1

3

Seedlings Seeds

IWMPRAISE

EU grant agreement Nº 727321

Five classes of IWM

10

IWM

Diverse cropping

systems (in space and

time)

Cultivar choice &

establishment

Field/soil management

Targeted control

Monitoring &

evaluation

IWM

Diverse cropping

systems (in space and

time)

Cultivar choice &

establishment

Field/soil management

Targeted control

Monitoring &

evaluation

Seed vigour

Spatial arrangement

11

Inter cropping

Rotation

Cultivar choice

Nutrient placement

Sowing depth

Trans-planting

Contact herbicides

Patch/band

sprayingBiocontrol

Sensing

technology

Scouting

DSS

Reducing impact of weeds on crop

Sowing date

Seed rate

Reduce seed return

Mechanical weeding

Flame weeding

Weed seed collection & destruction

Late herbicides

Liming

Hand weeding

Mowing

Prevent establishment

Cultivation depth

Cover crops

Pre-emergence herbicides

Seed bed preparation

Mulching dead

Mulching alive

Field margin management

Supportive tactics

Sowing pattern

Tillage type

Chemical sterilants

Water management

Stubble management

Five classes of IWM

12

IWM

Diverse cropping

systems (in space and

time)

Cultivar choice &

establishment

Field/soil management

Targeted control

Monitoring &

evaluation

Experimental site: diversified systems

Diversified systems in modern arable

farming? Is that possible?

Temporal & Spatial

18 ha field trial on clay soil

15

Field experiment

16

• Temporal Crop diversification

• Varieties resistant or tolerant to pests and diseases, weed suppressive traits

• Biological, Green Control or reduced chemical control based on DSS

• Monitoring & Evaluation

• Flower strips

IWM

Diverse croppin

g systems (in space and

time)Cultivar choice &

establishment

Field/soil manage

ment

Targeted

control

Monitoring &

evaluation

Start: 2018

Grote velden: 24 x 60 m

Total area ca 15 ha

10 ha netto field

17 >

spuitspoor 25

<

24m

>

spuitspoor 24

<

24m

>

spuitspoor 23

<

24m

>

spuitspoor 22

<

24m

>

spuitspoor 21

<

24m

>

spuitspoor 20

<

24m

>

spuitspoor 19

<

24m

>

spuitspoor 18

<

24m

>

spuitspoor 17

<

24m

>

spuitspoor 16

<

24m

>

spuitspoor 15

<

24m

>

spuitspoor 14

<

24m

spuitspoor 13

>

spuitspoor 12

<

24m

>

spuitspoor 11

<

24m

>

spuitspoor 10

<

24m

>

spuitspoor 9

<

24m

>

spuitspoor 8

<

24m

>

spuitspoor 7

<

24m

>

spuitspoor 6

<

24m

>

spuitspoor 5

<

24m

>

spuitspoor 4

<

24m

>

spuitspoor 3

<

24m

>

spuitspoor 2

<

24m

>

spuitspoor 1

<

24m

< 60m  > < 30m > < 60m  > < 30m > < 60m  >

23

Ui4-

47

Aa5 8+71

Ui8-

24

Pn8-

48

Sb8+72

Pn8-

22

Gr4-

46

Sk8+70

Gr8-

21

Ui8-

45

Aa4+69

Ui4-

20

Gr8-

44

Sb4+68

Gr4-

19

Gk8-

43

Aa1 8+67

Gk8-

18

Aa1 8-

42

Gr8+66

Aa1 8-

17

Sb8-

41

Gk8+65

Sb4-

16

Aa4-

40

Pn8+64

Aa5 8-

15

Sb4-

39

Ui4+63

Sb8-

14

Aa5 8-

38

Gr4+62

Aa4-

13

Sk8-

37

Ui8+61

Sk8-

IV V VI

12

Aa4+

36

Ui4-

60

Gr8+

11

Sb4+

35

Gr4-

59

Gk8+

10

Aa5 8+

34

Ui8-

58

Gr4+

9

Sk8+

33

Gr8-

57

Ui4+

8

Aa1 8+

32

Gk8-

56

Pn8+

7

Sb8+

31

Pn8-

55

Ui8+

6

Gk8+

30

Sb8-

54

Aa5 8+

5

Pn8+

29

Aa5 8-

53

Sk8+

4

Ui4+

28

Sk8-

52

Aa1 8+

3

Gr4+

27

Aa1 8-

51

Sb8+

2

Ui8+

26

Sb4-

50

Aa4+

1

Gr8+

25

Aa4-

49

Sb4+< kopakker 21m >

I II III

288m

Obj Middel

AA1 8- Aardappel

AA1 8+ Aardappel

AA4- Aardappel

AA4+ Aardappel

AA5 8- Aardappel

AA5 8+ Aardappel

GK8- Grasklaver

GK8+ Grasklaver

GR4- Wintertarwe

GR4+ Wintertarwe

GR8- Wintertarwe

GR8+ Wintertarwe

PN8- Peen

PN8+ Peen

SB4- Suikerbiet

SB4+ Suikerbiet

SB8- Suikerbiet

SB8+ Suikerbiet

SK8- Sluitkool

SK8+ Sluitkool met bloemenstrook

UI4- Zaaiui

UI4+ Zaaiui

UI8- Zaaiui

UI8+ Zaaiui

Teeltplan 2019

Two management systems:

Integrated crop management (+) mechanical based weed management

reference (-) herbicide based treatment

Prestatie indicatoren

Crop Yields notsignificantly different in first year

Weeds: notsignificantly different

Higher costs for weed management (labour)

Lower costs for diseasecontrol

18

0

0.2

0.4

0.6

0.8

1

icm icm 4 year rotation icm icm 8 year rotation

reference reference 4 year rotation reference reference 8 year rotation

Strip cropping, Erf Almere: 40 ha

1.21-1.58

Intercrop system LER

Wheat/maize

Wheat/soybean

Faba bean/maize

2

2

1

1LERM

Y

M

Y

Performance characterized by Land Equivalent Ratio = sum of the relative yields

Yi: yield crop i in intercropMi: yield crop i in sole crop

LER = land area that would be needed as sole crops to produce the same yield as a unit area of intercrop

1.23-1.26

1.13-1.34

Fang Gou, 2016

Crop diversity

and CA increase

population of soil

dwellers

Tamburini et al 2015. , Journal of Applied Ecology 53(1):n/a-n/a ·

Shuang Xie, 2015. Master thesis WU-FSE

0

10

20

30

0 10 20 30

infection score in strip (%)

In

fecti

on

score (

%)

gro

ots

ch

alig

em

on

ocu

ltu

ur(%

)

year2010

2012

2013

2014

2015

2016

In strip lower P. infestans infection22

Variety : Ditta

strip: 3m

Take home message:

1.Wider crop rotation leads to a

strong reduction in weed seed bank

density

2. Spatial diversity has positive

effects on disease and pest

incidence, effects on weed

management unclear

(Liebman et al 2016.)

Diverse cropping systems

(in space and time)

Five classes of IWM

24

IWM

Diverse cropping

systems (in space and

time)

Cultivar choice &

establishment

Field/soil management

Targeted control

Monitoring &

evaluation

Cover Crops & weeds

1. Competition for light, water and space

2. Allelopathic effects

25

Cultivar choice

Cover Crop Traits relevant for Weed Management

Cover crop Soil coverage Cold tolerant

Tagetes 5 1

Raphanus sativus 9 3

Avena strigosa 10 (excellent) 5

Allelopathy

Processes in which secondary metabolites are produced by plants, micro-organisms, and viruses that influence

the growth of plants.

Cover Crops

Two sources of allelochemical compounds:

● Direct from (cover) crop residues

● Indirect, produced by micro-organisms thatgrow on (cover) crop residues

Fases in the allelopathic proces:

1. Allelochemical compounds in the cover crop

2. Allelochemical compounds in the soil

3. Allelochemical compounds in the receptor plant (weed)

4. Effect of allelochemical compounds on the plant

(Kruidhof et al., 2007)

1. Allelochemical compounds in the cover crop

Quantities vary between cover cropspecies

Quantities are not stable during thegrowing season and vary withconditions and growth stage.

2. Allelochemical compounds in the soil

Release of compounds:

● Pre treatment of cover crop before soilincorporation

● Brake down of cover crop residues afterincorporation in the soil

In the soil compounds are converted, transported, or bound to soil particles.

This is influenced by :

● Physical soil qualities

● Chemical properties of the particles

● Soil moisture and temperature

Uptake is determined by the distance of the compound tothe root or the seed of the weed: good distribution in thesoil is important.

3. Allelochemical compounds in target plant

4. Effect of allelochemical compounds on the

weed

Depends on:

● Mode of action of the compound;

● Possibility of the weed to brake down harmfullcompound;

● Tolerance of the weed for the compounds;

● Growth conditions

The use of cover crops

In late summer and fall: prevent growth and seed production of weeds through competition

In spring: residues can suppress or delay weed development.

Effect of cover crop on weed growth in fall

and weed emergence in spring Soil: sandy, Organic matter: 4%.

species Sowingdate

Sowing density(kg/ha)

Alfalfa 25 July 25

Lupine 24 July 160

Brassica napus 25 July 7

Raphanussativus

25 July 15

Winter rye 25 July 150

Italian ryegrass 24 July 30

Incorporationof cover crops on March 31st.

Kruidhof et al 2007

Late summer and fall

Big differences in weed suppressive ability of cover crops

T50 Dry weight weeds (g/plant)

Control 6.01

Winterhardy Winterrye 33 0.80

Alfalfa 46 4.12

Brassica napus

28 0.22

Not winterhardy

Italian rye 50 2.54

White lupine 53 2.32

Brassica napus

27 0.27

T50= number of days until 50% soil coverage Kruidhof et al 2007

Spring

Dominant weeds: Chenopodium album

Alfalfa had the strongest effect in spring, followed by Brassica napusand Lupine

Winterrye and Raphanus did not suprres weed emergence in spring

0

0.1

0.2

0.3

0.4

0.5

0.6

cont

role

blad

ram

men

as

luze

rne

lupine

win

terk

oolzaa

d

win

terrog

ge

op

ko

mst

on

kru

iden

(%

)

Take home message:

Cultivar choice is relevant for

a) weed suppression and competition, look for soil coverage,

early growth, winterhardy crops;

b) Use the allelopathic effects of crop residues. Best effect of

incorporation just before rain

Cultivar Choice

Five classes of IWM

38

IWM

Diverse cropping

systems (in space and

time)

Cultivar choice &

establishment

Field/soil management

Targeted control

Monitoring &

evaluation

Cultivation

Field/soil management

Plough

Strip cultivation

‘Direct Sow

Start: 2009, maize based system

Experience with tillage types in arable

cropping system

Riemens, Weide, Van Schooten, Deru, Huiting et al 2016

Code Description

Main cultivationSowing bed

preparationSowing method

APlough Spring 25

cmrotary harrow

conventional

sowing

CDeep tine

cultivationrotary cultivator

conventional

sowing

DStrip rotary

cultivation

Strip rotary

cultivationstrip sowing

EDeep tine

cultivation

None (direct

sowing)direct sowing

Weed control

I Conventional

II Mechanical

Experiences with soil cultivation effects on

weed management

Results

A: plough + rotary harrow seed bed,

C: Deep tine cultivation + rotary harrow seed bed,

D:Strip Rotary cultivation + strip rotary seed bed,

E: Deep tine cultivation + direct sow.

Treatment I: conventional herbicidal based weed control, Treatment II: mechanical weed control.

Seed bank in spring 2018

Trials with stale seedbed

Crop: Lettuce

3 fields at experimental farm

jaar

eigenschap 1 2 3

% klei 16 14 14

% organische stof

2 1.9 1.8

voorvrucht Winter tarwe

Winter tarwe

zomergerst

plantdatum June 15

June 9 June 11

oogstdatum July 26 aug-01 July 30

Afstand in de rij (cm)

35 35 35

Afstand tussen de rij (cm)

37 37 37

veldgrootte (m)

154 x 20

172 x 20

136 x 20

Riemens et al 2007

Treatments

treatment Stale seedibed Seedbed prep Weed control before planting

Weed control after planting

A - Rotary harrow - -

B - Rotary harrow chemical -

C - Rotary harrow - torsionweeder

D - Rotary harrow - fingerweeder

E - Rotary harrow - harrow

F 4 weeks, rotary harrow

- chemical -

G 4 weeks, rotary harrow

- Rotary harrow -

H 4 weeks, rotary harrow

- Covered harrow -

I 4 weeks, rotary harrow

- Covered harrow -

Far red light

J - Covered harrow - -

Results

Reduction (%)

treatment Year 1 Year 2 Year 3

A 0 0 0

B 59.3 70.5 68.9

C 95.5 96.4 N.T.

D 98.7 99.2 N.T.

E 88.4 92.6 N.T.

F 69.2 67.5 74

G 43.2 59.9 70.7

H 73.7 71.1 80.2

I N.T. 71.1 82.8

J N.T. 63.1 61.5

Herbicidal control

Stale zaaibed behandelingen

Without stale seedbed

Mechanical control after planting

Mechanical control before planting

A: controlB: herbicideC: torsionweederD: fingerweederE: hoeF: herbicideG: rotory harrowH: covered harrowI: covered harrow + far red lightJ: covered harrow

Take home message

Field/soil management

• Inversion tillage valuable basis for weed management• Stale seed bed reduces weed growth during crop

growth - 43 tot 83%• Mechanical control of weeds emerging after stale

seedbed treatment causes new flushes better to use non soil disturbing tools (eg flame weeder)

• Mechanical control with fingerweeder, torsionweederand harrow reduced weed pressure with 88 to 99% relative to control.

From full field control to

control on the spot

47

TARGETED CONTROL

Full field;

Harrow

Non selective

Small seedlings

Application:

● Between sowing and crop emergence

● Firmly rooted crop

Interrow;

Hoe

Every cm closer to the crop row ways out a reduction in driving speed.

Application possibilities

● Vertually unlimited

● Combined with ridges

Intrarow: Torsionweeders

Fingerweeders

More precision with guidance systems

Physical guidance

● Rosko

Optical

● Robocrop Garford

● Steketee IC Weeder

● Auto-pilot Kress

Mechanical: Rosko

Based on fysical guidance from

the crop

Cheap

Engineered for maize, but several applications possible

Based on high speed

Optical systems

Robocrop

Roterende schoffel

Steketee IC weedmachine

Cameras view the crop from above

Camera is activated with a support wheel

mounted to the machine

Special software “traces” the plants

● Colour algorithm (Excessive Green)

● 2 * G – R – B

● Binar image

How does the software works?

Practical problem:weeds are also “plant pixels”

However:Location/pattern of weeds

deviates

Solution:Detect the consistency of

the seed pattern

Method: Fast-Fourier Transformation (patent Wageningen UR)

Intelligent intra-row weeding

59

Robovator Poulsen in lettuce

www.visionweeding.com

Intrarow flame weeding

Slow motion intrarijbrander Poulsen

Broadleaf weeds in grassland

Robot Ruud: dock in grassland

63

www.ruud.wur.nl

AgroIntelli

64

Plant level, on-the-go, autonomous 65

IWM

Diverse cropping

systems (in space and

time)

Cultivar choice &

establishment

Field/soil management

Targeted control

Monitoring &

evaluation

Seed vigour

Spatial arrangement

66

Inter cropping

Rotation

Cultivar choice

Nutrient placement

Sowing depth

Trans-planting

Biocontrol

Sensing

technology

Scouting

DSS

Reducing impact of weeds on crop

Sowing date

Seed rate

Reduce seed return

Mechanical weeding

Flame weeding

Weed seed collection & destruction

Liming

Hand weeding

Mowing

Prevent establishment

Cultivation depth

Cover crops

Pre-emergence herbicide in

spring

Seed bed preparation

Mulching dead

Mulching alive

Field margin management

Supportive tactics

Sowing pattern

Tillage type

Crop destruction

with herbicides

Water management

Stubble management

Post-emergence herbicide in

autumn

Patch/band spraying

Pre-emergence herbicides

Pre-sowing herbicides

www.IWMPRAISE.EU

Vision provides new possibilities

for DSSWeed recognition and image processing

Calculation of in field weed pressure & mapping

67

Monitoring & DSS

www.akkerweb.nl: platform for farmers, also in english

What’s going on here?

What can I do?

What should I do?

What would I like to do?

Weather Soil

Crop

Weed

Bio

ph

ysic

al

Economic Technological

Financial means

Cost-benefit Time

investment

Efficacy

Regulations

Individual

Socio

-cultu

ral

Flexibility

World view

Experience

Public perception

Technological means

Farmers are the key: success of IWM in practice

www.IWMPRAISE.EU

IWMPRAISE partnerswww.iwmpraise.eu

Physical and Cultural Weed Control-

European Network

EWRS: www.ewrs.org/pwc, or

marleen.riemens@wur.nl

+31 317 410610

Thanks are due to Rommie van der Weide, Hilfred Huiting, Pieter Blok, Frits van Evert,

Dirk van Apeldoorn, Leendert Molendijk, Corne Kempenaar, Paula Westerman, Mout de

Vrieze, Huub Schepers, Fogelina Cuperus, Wijnand Sukkel, Bram Veldhuisen, Johnny

Visser