CropManage: Online Irrigation and Nutrient Management ToolManagement Tool 

Web‐Based Software for Lettuce Production

Michael CahnIrrigation and Water Resources AdvisorUniversity of California, Cooperative, Monterey Co

Acknowledgements

Tim Hartz Richard SmithTim Hartz, Richard SmithCalifornia Department of Food and Agriculture, Fertilizer Research and Education ProgramFertilizer Research  and Education ProgramUC ANR Communication Services, Bryon NoelGrower participantsGrower participantsChiquita FreshExpressTanimura and AntleTanimura and Antle

Lower Salinas Nutrient TMDLSalinas Valley Basin Plan

Ag OrderSWRCB SBX2 1

Tools for Managing Water and Nitrogen F ili i LFertilizer in Lettuce

soil nitrate quick test  (20 NO N 70 80 lb f N/ /f )(20 ppm NO3‐N = 70 to 80 lbs of  N/acre/ft) 

Weather‐based irrigation scheduling

Commercial Lettuce Nitrogen Fertilizer Trials

2 0

300 Standard BMP

d lb /200

250

/A

Std:     212 lbs N/AcreBMP:  146 lbs N/Acre

100

150

lbs

N

Difference 66 lbs/A

0

50 30% reduction in N fertilizer

0

1 2 3 4 5 6 AveField

Applied Water as Percentage of Crop ET (Lettuce)

) 300

350Crop ET (Lettuce)

Cro

p ET

)

250

300 Avg Applied Water = 176% of Crop ET

ater

(% C

150

200

pplie

d W

a

100

150

Ap

0

50

Field Number

1 3 5 7 9 11 13 15 17 19

Weather‐based Irrigation Scheduling

Converting Reference ET to Crop ET:

ETcrop = ETref × Kcrop

Kc can vary from 0.1 to 1.2

CIMIS weather networkCIMIS weather network

29 DAP 41 DAP

1.0sprinkler irrigation events

Estimated Kc of Lettuceie

nt (K

c)

0 6

0.8

47 DAP 65 DAP

op C

oeffi

c

0.4

0.6

SprinklerDrip

Cro

0.0

0.2 Average Kc = 0.33 during germination with sprinklers

Days after Planting

0 20 40 60 80

Other information needs to be consideredIrrigation System UniformityIrrigation System Uniformity

and Application RateRooting Depth

Salinity of Water SourceSoil Type

How can water and N management tools be useful for large vegetable growing operations?useful for large vegetable growing operations?

Large growing operations have multiple decision makersmakers One farm manager may be responsible for >200 fields during a seasonfields during a seasonOther responsibilities besides water and fertilizer N managementN management

Web‐based Irrigation and N management  software for lettuce

https://ucanr.edu/cropmanage

CropManage Web‐based Tool:Assist growers in making decisions on irrigation and nitrogen fertilizer management

Intuitive, simple, quick to use.Accessible from smart phone, tablet computer,Accessible from smart phone, tablet computer, 

desktop computerGuide irrigation schedules using CIMIS weatherGuide irrigation schedules using CIMIS weather 

data. Guide nitrogen fertilization decisions using quickGuide nitrogen fertilization decisions using quick 

nitrate test data.Maintain and share irrigation, fertilizer, and soilMaintain and share irrigation, fertilizer, and soil 

test records for multiple fields and farms.

Integrate information from multiple sources

Crop ET modelWatering Recommendation

Soil and Ranch

Database driven web  N fertilizer 

Recommendationapplication

Crop N model

RecommendationCIMIS ETo

Record display and data export

Field sensorsSoil nitrate test

p

Decision support using crop models

How is N fertilizer rate determinedHow is N fertilizer rate determined from the quick nitrate test?

Future Crop N uptakeFertilizer N =

– (Quick Test N  ‐ threshold NO3‐N) 

– Soil mineralization N 

– Plant residue N

80

100

80

100Iceberg lettuce canopy cover

(%)

80

100

Canopyobs = 1.01 x Canopypred - 0.69(%)

80

100

Canopyobs = 1.01 x Canopypred - 0.69

py C

over

(%)

40

60

80

py C

over

(%)

40

60

80

Can

opy

Cov

er

40

60

80 p

R2=0.99

Can

opy

Cov

er

40

60

80 p

R2=0.99

Can

op

0

20

40

Can

op

0

20

40

Obs

erve

d C

0

20

40

Obs

erve

d C

0

20

40

Days after Planting

0 10 20 30 40 50 60 700

Days after Planting

0 10 20 30 40 50 60 700

Predicted Canopy Cover (%)

0 20 40 60 80 1000

Predicted Canopy Cover (%)

0 20 40 60 80 1000

Spatial CIMIS ETo Reporting

Interface with UCD SoilWeb Tool

How much water was applied?

Evaluate and Document Water Management

s) 12s) 16

er (i

nche

s

10

12

CropManage RecommendationGrower Application

er (i

nche

s

12

14

16

CropManage RecommendationGrower Application

ied

Wat

e

6

8

ied

Wat

e

8

10

12

tive

Appl

i

4

tive

App

l

4

6

Cum

ulat

0

2

Cum

ulat

0

2

Days after Planting

0 10 20 30 40 50 60Days after Planting

0 10 20 30 40 50 60

Steps to Using CropManageSteps to Using CropManage

1. Establish User Login2. Assign to Ranch or start New 

Ranch3. View Planting within Ranch or 

Add New Planting4. View or enter soil tests, fertilizer, 

or irrigation events

UC Security and Privacy Policy

1. CropManage is designed to protect the privacy of grower data.

2. Current industry security standards are used (backed up to 2 other servers, encryption, secure security socket layer).

3. UC does not give out/sell grower data and is not obligated to give out data.

4. UC will not analyze grower data without first asking for permission.   

Ranch Summary

Soil Summary

Fertilizer Summary

Water Summary Table

Field Validation of CropManage

Treatment sprinkler drip1Applied water Commercial 

YieldTreatment sprinkler driplbs/acre

Grower Standard 4.1 4.9 17935inches

Yield

CropManage 4.1 3.8 183891 comparison was on last 7 irrigations

TreatmentApplied N Fertilizer

Commercial Yield

------- lbs per acre --------Grower Standard 211 19114CropManage 149 18760

The road ahead…

Soil moisture monitoring

)

0

sion

(cba

rs10

istu

re te

ns

20

soil

mo 30 8 inches

18 inches

Date

9-16 9-18 9-20 9-22 9-24 9-26 9-28 9-30 40

User Support: CropManage Blog

Final Thoughts

Web applications can repackage complex data sets andWeb applications can repackage complex data sets and mathematical models  into simple to use decision support tools

CropManage is not just for growers.  It is a potential tool f lfor crop consultants and advisers to use in assisting growers with water and N management decisions.

We will offer 2 hour training workshops on CropManage on March 13 and April 2, 2013.p ,