Adapting CropManage for Oxnard

Andre Biscaro, Irrigation and Water Resources Advisor,

Ventura, Los Angeles and San Bernardino Counties

Objective

Assess CropManage’s water and nitrogen fertilizer recommendations

*Strawberry (2) and celery (2)

Previous Year Measurements 2014/15 season:

• 6 strawberry fields (2 varieties)

• 2 celery fields

• 3 raspberry fields

• 4 sampling locations per field

Monthly:

• Aboveground biomass and nutrient content (NPK)

• Canopy cover (%)

• Root depth

• Soil mineral nitrogen

Yield and fertilizer records from participating growers

Canopy Cover

• 20, 60 and 80%

20%

60%

80%

Canopy Cover

0

20

40

60

80

100

0 50 100 150 200 250

%

DAP

Root Depth

0

4

8

12

16

20

0 50 100 150 200 250

Inch

es

DAP

Aboveground Biomass N Uptake

0

50

100

150

200

250

300

0 50 100 150 200 250 300

Lbs

N/A

DAP

1 2 3 4

Study 1, Strawberry

Design

CM

na na

D

na

D CM

na plot # 102 402 602 702

D CM CM D

plot # 101 401 601 701

Road

Planting date: October 17th

68” bed 3 tapes Fruit yield est.: 71,333 lbs/A

Oct – March: same water and N fert.

0

20

40

60

80

100

CM GS Predicted

Canopy Cover (%)

Drip Irrigation (Feb-Jun, Weekly Total)

0.0

0.4

0.8

1.2

1.6

2.0

Inch

D CM

AF

D CM 2.1 2.4

Recommended vs Applied Water (CM treatment)

0

2

4

6

8

10

12

14

Inch

es

Recommended Applied

Soil Moisture (cb)

0

10

20

30

6"CM 6"D

0

40

80

120

160

200

D CM

Nitrogen Fertilizer Applied (Lbs/A)

N Recomm. CM Applied GS Applied

----- lbs N/A ----

Oct - Mar --- 72 72

9-Mar 22 7 2

18-Mar 14 10 3

25-Mar 9 6 4

1-Apr 8 2 2

6-Apr 17 6 10

11-Apr 19 9 4

19-Apr 19 10 4

29-Apr 14 10 4

3-May 14 14 6

11-May 12 12 6

20-May 9 9 8

25-May 8 8 5

164 103 59

Total ? 175 130

Soil NO3-N (ppm)

0

2

4

6

8

10

12

D CM

Marketable Yield

0

1000

2000

3000

4000

5000

6000

Lb/a

c CM D

Results

GS CM

Total yield (lbs/A) 100%(a) 122.3%(b)

Cull (Avg %) 28 27

Albino (%) 2 1

Water use (AF) 2.1 2.4

N fertilizer use (lbs N /A) 130 175

Veg biomass at harvest (g/plant) 542 1,047

Field Day

Strawberry Study 2

14 acres each

*Cultivar not studied the year before

Irrigation (April – May)

0.0

0.1

0.2

0.3

0.4

0.5

in

CM GS

Total N Fert (lbs/A)

GS 100

CM 65

Trays CM Control

17-Apr 1,590 1,435 24-Apr 1,770 1,733 1-May 1,680 1,797 5-May 1,478 1,034 8-May 2,246 2,460

15-May 2,586 2,633

Total

11,350 11,092

35% less N fertilizer

(Mar – Jun)

Celery Study

• Previous crop: cabbage

• Planted: Jan 22

• Harvested: May 17

• 117 days

• 2 rows/bed

• 1 low flow tape @ center of the bed

Design

2 treatments: - Grower Standard (1)

- CropManage (2)

1 21 2 2 1 2 1

(3 beds/plot)

777ft long

0

50

100

150

200

250

NApplied NRecommended

Nitrogen Fertilizer (lbs/A) (CM treatment)

In-season N Fertilizer (Fertigation)

0

100

200

300

GS CM

24% less (75 lbs/A)

Lbs/

A

11

32

32

Total (lbs N/A) 312 vs 236

Soil Nitrate-N (ppm) SNQT, 0-12in

0

10

20

30

40

50

CM GS

Soil NO3-N at Harvest (ppm) 0-12in

Soil NO3-N at Harvest (ppm) 12-24in

0

0.2

0.4

0.6

0.8

1

1.2

1.4

in

GS CM

Irrigation Acre-inch

GS CM 13.6 13.8

0

0.4

0.8

1.2

1.6Requested Applied

Amount Requested vs Amount Applied

(May 17 = harvest)

Soil Moisture

0

20

40

60

80

100

Ce

nti

bar

s

8" GS 8" CM

Low Uniformity

Canopy Cover (%)

0

20

40

60

80

100

120

CM GS

Marketable yield GS CM

--- lbs/A ---

79,926 83,282 -- Boxes/A --

1,308 1,384

(Differences are not statistically significant)

Marketable Yield

Grower Standard BMP

Celery 2

GS CM

Water (AF) 1.1 0.85

N Fertilizer (lbs/A) 223 200

Yield (lbs/20ft) 165.5 166.7

Yield (lbs/20ft)

Spad

Celery 3 (ongoing)

Strawberry 3, 4 and 5 (ongoing)

Summary

Study # Crop Yield relative to

grower standard

Water use relative to

grower standard

Fertilizer (lbs N/A) use

relative to grower

standard

1 Strawberry 22% higher 14% higher 34% higher

2 Strawberry 2% higher* Same 35 % lower

3 Celery 5% higher* Same 24% lower

4 Celery same 22% lower 10% lower

*not statistically significant

Final Thoughts

• CropManage showed to be efficient in guiding irrigation and N fertilization

• Algorithms for water and N need improvement/fine-tuning

• Although not perfect, it’s a more comprehensive approach than usual fertilization “program” and fixed irrigation schedule

• CropManage did not decrease yield

Questions/comments?