0. Variable Rate Irrigation Approach for Wine Grapes in California
Luis Sanchez
California Irrigation Institute Conference
Sacramento, January 26, 2016

1. 5x yield differences in the same row
Variable vineyards
5x yield differences in the same row
Plant Available Water
Colony 13 – Petite Sirah

2. How can we manage vineyard variability?
Through Precision Viticulture:
Management to optimize vineyard performance
Responding to field variability
Maximizing grape yield and quality
Minimizing environmental footprint

3. Precision Viticulture
Variable rate irrigation
Other crops:
Sensor-driven systems in nurseries
Center pivot systems in grain crops
Wine grapes: management zones
Australia (McClymont et al. 2012; Proffitt and Pearce 2004)
Spain (Bellvert et al. 2012; Martínez-Casasnovas et al. 2009)
….and California
Not flexible!

4. Soil 1
Zonal Irrigation
Soil 2

5. Irrigation management zone 1 Irrigation management zone 1
Zonal Irrigation
Irrigation management zone 1
VF PUMP

6. Irrigation management zone 1 Irrigation management zone 1
Zonal Irrigation
Irrigation management zone 1
Soil 3
VF PUMP

7. Soil 1
Modular Irrigation
Soil 2
Soil 3

8. Soil 1
Modular Irrigation
Soil 2
Soil 3
VF PUMP

9. Soil 1
Modular Irrigation
Soil 2
Soil 3
VF PUMP

10. Soil 1
Modular Irrigation
Soil 2
Soil 3
VF PUMP

11. Wine Program A
Modular Irrigation
Wine Program B
VF PUMP

12. Variable Rate Irrigation Study
Objective:
Develop and operate a proof-of-concept VRI system prototype and validate it by:
Decreasing vineyard variability
Optimizing fruit yield and quality
Maintaining/improving water use efficiency

13. Experiment location
Colony Ranch, Wilton CA

14. Colony 2A Cabernet Sauvignon
2012 yield map
Colony 2A Cabernet Sauvignon
Wilton, California
31.5 acres
5 x 11 feet
17-year old
Teleki 5C
Hand-pruned
Drip-irrigated
San Joaquin silt loam (~ 75%)
San Joaquin-Galt complex (~ 25%)
500 mm (20”) annual rainfall
Highly variable

15. Field layout 140 Irrigation Zones Variable rate VRI Conventional CI
Landsat data
30 meter
Variable rate
VRI
Conventional CI
140 Irrigation Zones

16. VRI General layout
Variable Flow Pump

17. VRI System design Tubing, 0.69”ID 4” Solenoid Power loc 2” adapter tee
Check
valve 2”
Solenoid
Power loc
adapter
tee
Tubing, 0.69”ID
emitters

18. VRI System design

19. Power distribution box
Control board
Power distribution box
Control
box
UPS
box
Cell
Antenna
480 VAC
115 VAC
Lightning arrestor
12 VDC to
14 subnets
Communications
to South and North

20. Variable rate irrigation scheduling
METRIC (Mapping evapotranspiration at high resolution and internalized calibration)
ET residual of surface energy balance
Rn + LE + G + H = 0
Inputs
Landsat (visible & infrared)
CIMIS weather data
Outputs
ETc
Kc (f/NDVI)
Watering of each zone: ETc * Km
(ETc = ETref * Kc)

21. But can default to #1 under severe water shortage
Variable rate irrigation scheduling
System can be used to:
Irrigate each zone according to vine size with-out altering natural variability  uniform Km
Apply more water to low vigor areas in order to increase vine size and yield and decrease vineyard variability  variable Km
We want #2!
But can default to #1 under severe water shortage

22. Irrigation management factor
Variable rate irrigation scheduling
# of irrigation zones
Irrigation management factor
May
4 weeks
June
4 weeks
July - Oct
16 weeks
140
0.0 – 1.0
0.5 – 0.8
0.6 – 1.0

23. Variable rate irrigation scheduling
Adjusting Km based on vine vigor
% maximum
5/24/15
6/25/15
7/27/15
8/25/15
Landsat NDVIs
NDVI = Normalized Difference Vegetation Index

24. Irrigation + rain received 3/1 thru 9/30
Acre feet

25. Variable rate (VRI) yield - Normalized
Mean = 8.9 t/a
6.1 – 12.4 t/a
Spread = 0.71
2013 Yield:
Mean = 7.7 t/a
6.3 – 8.9 t/a
Spread = 0.33
2014 Yield:
Mean = 10.1 t/a
6.2 – 14.0 t/a
Spread = 0.76
2015 Yield:
Mean = 5.1 t/a
4.2 – 6.7 t/a
Spread = 0.50

26. Conventional (CI) yield - Normalized
Mean = 8.9 t/a
6.4 – 10.9 t/a
Spread = 0.50
2013 Yield:
Mean = 7.4 t/a
5.8 – 10.7 t/a
Spread = 0.68
2014 Yield:
Mean = 8.7 t/a
6.1 – 14.3 t/a
Spread = 0.93
2015 Yield:
Mean = 4.6 t/a
3.1 – 8.8 t/a
Spread = 1.27

27. Yield and water use efficiency
Average 10%
Average 12%

28. Vine performance data 5-vine plots Yield components Vine physiology
Fruit composition/quality
Wine composition/quality

29. Fruit Yield and Quality
Increase in berry weight every year; 2015 increase in berries/cluster and clusters/vine

30. Conclusions
Modular variable rate drip irrigation system prototype was successfully implemented
Vineyard variability was manipulated with precision
Yield was increased during 3 seasons by an average of 10% with up to 17% gain in water use efficiency
Potential decreases in quality could be offset with standard canopy manipulations

31. Next step: 2nd generation system
System tested in Israel on wine grapes and citrus during 2015
All valves and controls outside the vine rows!

32. Livingston 5-yr old Malbec
Next step: 2nd generation system
Livingston 5-yr old Malbec
96 irrigation zones
30x30m each
24.4 acres
Includes VR fertilization

33. Next step: 2nd generation system
20-30% cost increase over commercial standard
Multiple vineyards
Other permanent crops

34. Acknowledgments E&J Gallo Winery
Viticulture Lab: Brent Sams, Maegan Salinas, Erin Troxell, George Zhuang, Cassandra Plank, Tian Tian, Cody Lichtfield, Nona Ebisuda
Chemistry: Hui Chong, Bruce Pan, Natalia Loscos, Bianca Wiens
Research Winery: David Santino
GVI-CV: Alan Reynolds, John Owens VII, Christopher Bach, Evan Goldman
GIS-CE: Andrew Morgan
Nick Dokoozlian
IBM (TJ Watson Lab & Data Center Services)
TJ Watson Lab, NY: Levente Klein, Nigel Hinds, Hendrik Hamann
Data Services, CA: Alan Claassen, David Lew
Netafim Israel: Avi Schweitzer, Itamar Nadav
James Taylor, New Castle University, UK
Ernie and Jeff Dosio, Pacific Agrilands
Scott Britten & Associates, Bennett & Bennett
Bernd Kleinlagel, ATV, Australia

35. Thank you!

36. Fruit Yield and Quality

37. 2014 Leafing study LV / NL = Low vigor, No Leafing
HV / L = High vigor, Leafing
LAI
HV / NL = High vigor, No Leafing

38. 2015 Leafing study LV / NL = Low vigor, No Leafing
HV / L = High vigor, Leafing
LAI
HV / NL = High vigor, No Leafing

39. Irrigation water use in CA wine grapes
Typically between 2 to 2.5 acre-feet/season
650,000 to 815,000 gallons per acre
For 10 ton/acre yield:
65,000 to 81,500 gallons/ton
WUE = 4 to 5 tons/acre-foot

40. 2nd generation system