Geoff Furness Research Scientist, Consultant, Spray Application Technology Geoff Furness is a scientist with 44 years experience with research interests in entomology, especially in citrus and viticulture, (IPM, ecology, and control) and spray application technology (air assisted sprayer design and evaluation in both horticulture and field crops). Geoff Retired from a 42 year career as a senior research scientist with the South Australian Research and Development Institute in Primary Industries and Resources, SA in 2010. He now works part time as a consulting scientist. Over the years he has developed informal research and development teams with private manufacturers and consulting engineers and designers to develop new concepts and products for air assisted spray application. He also does general consultancy work as requested. He was a major innovator in the development and evaluation of multi fan orchard and vineyard assisted sprayers and improved fan design for this new type of sprayer with the support of the wine industry and equipment manufacturers. These new sprayers are now a mainstream product in both Australia and a wide range of other countries. Another major project was the development and implementation of distance based spray calibration for tree crops and grapevines and the determination of the point of first run off using the unit Litres per 100m per m of canopy height which is vital for accurate dosing, especially with concentrate spraying. This work was the catalyst for the development of the new pesticide label format for Australia by the APVMA and AVCARE for tree and vine crops, and has created considerable interest internationally. He also developed the bluff plate sprayer for high speed, low volume, spray application to broad acre, dryland crops.

The Practical Way To Get Wet

Geoff Furness

Canopy Spraying

Optimum efficacy: • Timing

• Dose

• Coverage

Factors affecting amount of chemical impacted: • Chemical concentration (amount / 100L) – label rate

• Spray volume

Canopy Spraying

Canopy Spraying

Canopy Spraying

• New label format for Australia – Dilute rate: amount per 100 L

– Concentrate spraying has maximum concentration specified

– Chemical rate per hectare deleted

Canopy Spraying

• Distance calibration

• New mind shift

• Litres / 100m / m of canopy height

Canopy Spraying

80 to 120

60 to 90

40 to 60

20 to 30

Canopy Spraying

• Suggested maximum dilute spray volumes (wetness) for concentrate spraying L/100m/m

– Grapevines 20 - 30

– Fruit trees (general) 20 - 30

– Citrus 30 - 50

Canopy Spraying

Canopy Spraying

• Spray Volume Calculator (L / 100m of row)

l/min 3 km/h 4 km/h 5 km/h 6 km/h 7 km/h 8 km/h

6 12 9 7.2 6 5.1 4.5

10 20 15 12 10 8.6 7.5

14 28 21 16.8 14 12 10.5

18 36 27 22 18 15 14

22 44 33 26 22 19 17

26 52 39 31 26 22 20

30 60 45 36 30 26 23

Canopy Spraying

Other useful formulae – Length of row / hectare (m) = 10 000 ÷ row spacing (m)

– Number of tanks required =

total row length x spray volume ÷ volume of tank ÷ 100

(m) (litres/100m) (litres)

– Litres / hectare = litres / 100 m ÷ row spacing x 100

Canopy Spraying

A Visual droplet rating chart

Canopy Spraying

Canopy Spraying

Canopy Spraying

• UV dye droplets on almond fruit

Bottom, outer canopy

outward facing inward facing

Canopy Spraying

• UV dye droplets on almond leaves

bottom third of outer canopy top third of outer canopy

Canopy Spraying

Canopy Spraying

Canopy Spraying

0

200

400

600

800

1000

1200

0 50 100 150 200

Mea

n dr

ople

t num

ber

Spray Volume (L / 100m / m height)

Canopy Spraying

0

0.5

1

1.5

2

2.5

3

3.5

0 50 100 150 200

Dep

osit

(ul/c

m-2

x C

F)

Spray volume (L / 100m / m height)

Canopy Spraying - Current Treat

# Machine Tree

Height (m)

Canopy Height

(m)

Canopy Density

Nozzle Array

Spraying Speed

(km/hr)

Water Rate

(L/Ha)

1 Engine driven, twin fan airblast

9.2 7.7 Sparse/ Medium

Standard 5.5 1,470

2 Engine driven, twin fan airblast

9.2 7.7 Sparse/ Medium

Fine* 5.5 1,500

3 Engine driven, twin fan airblast

5.8 5.0 Medium Fine* 5.5 1,290

Canopy Spraying - Current Treat

# Machine Tree

Height (m)

Canopy Height

(m)

Canopy Density

Nozzle Array

Spraying Speed

(km/hr)

Water Rate

(L/Ha)

4 PTO driven, twin fan airblast

6.0 4.5 Medium Standard 5.5 1,200

5 PTO driven, twin fan airblast

6.0 4.5 Medium Fine* 5.5 1,200

6 PTO driven, single fan

airblast

6.0 4.5 Medium Standard 5.5 1,200

Canopy Spraying - Current

0

200

400

600

800

1000

1200

CT

CT

CB

N1

N2

N2

N3 S1

S2

S2

S3

E1

E2

E2

E3

E4

E5

E5

E6

W

1 W

2 W

2 W

3 W

4 W

5 W

5 W

6

Dro

plet

num

ber p

er c

m2

Position in canopy

Engine Driven Twin fan, standard nozzles 13L /100m /m canopy height

Canopy Spraying - Current

0

200

400

600

800

1000

1200

CT

CT

CB

N1

N2

N2

N3 S1

S2

S2

S3

E1

E2

E2

E3

E4

E5

E5

E6

W

1 W

2 W

2 W

3 W

4 W

5 W

5 W

6

Dro

plet

num

ber p

er c

m2

Position in canopy

Engine Driven Twin fan, fine nozzles 13L /100m /m canopy height

Canopy Spraying - Current

0

200

400

600

800

1000

1200

CT

CT

CB

N1

N2

N2

N3

N4

N5

N6

N6 S1

S2

S2

S3

S4

S5

S5

S6

E1

E2

E2

E3

E4

E5

E5

E6

W

1 W

2 W

2 W

3 W

4 W

5 W

5 W

6

Dro

plet

num

ber p

er c

m2

Position in canopy

Engine Driven Twin fan, fine nozzles 17L /100m /m canopy height

Canopy Spraying - Current

0

200

400

600

800

1000

1200

CT

CT

CB

N1

N2

N2

N3 S1

S2

S2

S3

E1

E2

E2

E3

E4

E5

E5

E6

W

1 W

2 W

2 W

3 W

4 W

5 W

5 W

6

Dro

plet

num

ber p

er c

m2

Position in canopy

PTO Driven Twin Fan, Std coarse nozzles 20L /100m/m canopy height

Canopy Spraying - Current

Key points learnt so far

• Engine driven twin fan – Less than 17L /100m /m canopy height is below even point of

runoff

– 20L /100m /m canopy height is suggested to achieve even point of runoff

• PTO driven twin or single fan – 19L /100m /m canopy height is below even point of runoff

Canopy Spraying - Next Treat # Machine L/100m/m

tree height

Spraying Speed

(km/hr)

Canopy Height (m)

Water Rate (L/Ha)

* estimated 1 Engine driven, twin

fan airblast 20 3 7.7 2,300*

2 Engine driven, twin fan airblast

20 5.5 7.7 2,300*

3 Engine driven, twin fan airblast

20 8 7.7 2,300*

4 PTO driven, twin fan airblast

25 5.5 4.5 1,500*

5 PTO driven, twin fan airblast

30 5.5 4.5 1,862*

6 PTO driven, twin fan airblast

35 5.5 4.5 2,200*

Canopy Spraying

Canopy Spraying

Canopy Spraying

• Air & Coverage –Large volume

–Low velocity

–High turbulence

–Air profile and targeting

• Air & Power –Large volume at low

velocity

–No ducting and bending

–No pressurising

Canopy Spraying

Spray Drift

Spray Drift

• Fate of spray droplets

Body of table: L/100m-1 Red Scale hand

wand Oscillating

Boom Airblast

Amount applied 775 665 386

Calculated tree capacity 366 366 403

Estimated total amount sprayed on trees (including branches)

324 317 210

Volume on ground 444 175 15

Balance 8 173 161

Spray Drift

• Reducing spray drift – Increase droplet size

– Turn off nozzles not aimed at the canopy

– Match air volume to the canopy

– Match air and spray profile to the canopy

– Alter spraying speed

– Turn off air on end row

Spray Drift

• Reducing soil contamination – Decrease droplet size

– Use lower spray volumes

– Match air and spray profile to the canopy

Thank You