A presentation about nitrogen in cranberry agriculture in Massachusetts. Presented by Carolyn DeMoranville of the UMass Cranberry Station during the Buzzards Bay Coalition's 2013 Decision Makers Workshop series. Learn more at www.savebuzzardsbay.org/DecisionMakers

1. Nitrogen in Cranberry
Agriculture
Carolyn DeMoranville, UMass
UMass Cranberry Station

2. Why cranberry farmers use nitrogen
 Important in plant structure
and function
• Protein, DNA
• Chlorophyll
 Each year the plant makes more leaves, stems,
and roots and sheds leaves and roots
 In the fruit, N is the element in the highest
concentration
 Nitrogen is arguably the most important fertilizer
element applied to cranberries
UMass Cranberry Station 2

3. N removed (pounds/acre per year) - Early Black
Nutrient Removed- Removed – Total
leaves/ 100 bbl crop
stems*
Nitrogen 13.6 5.0 18.6
Since Early Black has small leaves
*Leaves and stems and thin stems compared to hybrids,
are removed as part there is an assumption that N removal
of harvest operations for those would be greater. This
calculation does not include N in
roots.
UMass Cranberry Station 3

4. How much N is required?
 At least enough to replace what’s lost and
to support new growth and fruiting
 Cranberry varieties have differing needs
for N – larger fruit, larger plants (leaves)
and bigger crops mean more N is needed
 Most growers develop
fertilizer programs based
on N.
UMass Cranberry Station 4

5. How cranberries get nitrogen
 From soil
• Cranberry soil very sandy - holds little
• Organic matter - 1-2% only
 From recycling in the plant
• Some stored in stems and roots
 From fertilizer
UMass Cranberry Station 5

6. Compare cranberry to other crops
Plant leaf tissue Avg. applied
Crop Nitrogen (%) Nitrogen (lb)
Cranberry 0.9-1.1 20-60
Blueberry 1.0-1.5 45-65
Apple 2.0-2.5 50-60
Peach 2.5-3.0 80
Corn 2.9-3.5 160-200
Wheat 2.6-4.0 75-110
UMass Cranberry Station 6

7. Nitrogen use in cranberry
 If growers get N
wrong – they pay
a price in plant
growth and crop
 There is a body of
research on N
needs and rates
UMass Cranberry Station 7

8. Disadvantage to too much N
UMass Cranberry Station Davenport, Stevens in BC 8

9. N rate decision tree – from the BMPs
 Use less N if:  Use more N if:
• No or low crop • Bog renovated or new
• Native varieties • Ben Lear or Stevens
• Deep peat • Mineral soil
• >3% organic • <1% organic
• You sanded • You mowed
• You pruned • Crop was heavy
• Tissue N >1.1% • Tissue N <0.75%
• Uprights long/runners • Uprights stunted/thin
• Frost damage • Heavy bloom
• Insect/disease damage • General yellowing
UMass Cranberry Station 9

10. Nitrogen Form - Ammonium
 Several studies show best growth and N
uptake with ammonium (compared to nitrate)
 Ammonium taken up 10x faster than nitrate
 Little conversion of ammonium to nitrate at
low pH; ammonium leaches less
UMass Cranberry Station 10

11. Nitrogen – Nitrogen Cycle
 Ammonium
 Soil T
 Low pH
 Removal in Fertilizer
crop
(~23 lb in
150 bbl)

12. When do cranberries need nutritional support?
 Applications
coincide with
growth and fruiting
demands of the
plants
 Late May through
early August
UMass Cranberry Station 12

13. Environmental considerations
 Biggest concern is movement of N in
surface water
 Leaching limited
• layered soil and barrier layers (why the
bog can hold a flood)
• ammonium N forms
 Groundwater
pathway – total
extent unknown
UMass Cranberry Station 13

14. Flooding practices
UMass Cranberry Station 14

15. CES/SMAST Field Study
Cranberry Bog NET Nitrogen Loss
Bog ID --> EH PV BEN WS M-K ASH
Nitrogen Inflow to Bog
Irrigation 0.4 1.5 0.6 0.2 1.7 2.4
Groundwater 0.0 0.0 1.0 0.3 0.0 0.0
Frost Protection 0.8 1.8 1.4 0.5 1.6 2.0
Pest Management 0.0 0.2 0.1 0.1 0.1 0.1
Harvest 1.3 3.4 4.5 1.2 4.2 2.9
Winter Protection 3.0 3.7 5.2 1.4 4.8 4.0
Total IN 5.5 10.5 12.8 3.6 12.4 11.3
Nitrogen Outflow from Bog
Drainage/Infiltration 5.7 6.7 10.5 4.6 7.7 7.2
Harvest 2.1 5.3 9.4 4.3 4.5 2.8
Winter 4.0 4.6 6.4 1.7 4.0 5.2
Total OUT 11.9 16.5 26.3 10.5 16.2 15.2
Net Nitrogen Loss (lb/a/yr)= 6.4 6.0 13.5 7.0 3.7 3.8
Nitrogen Output to Downgradient Systems (lb N/acre/yr)
Pine-Oak Forest 0.4
Cranberry Bog Nitrogen Output 6.4 (Flow Through Bog = 8.6)
Residential (density 1 per 2.5 acres) 5.7
Direct Precipitation on Bay 9.8

16. How can we reduce N output?
 Practice BMPs regarding rate, timing, split
applications
 Look at it more as a water problem
• Amount of flow
• Direction of flow
• Pathway of flow
UMass Cranberry Station 16

17. Amount of flow
 Follow recommendations on flooding,
drainage, and irrigation
 Research on looking at how to limit
groundwater upwelling
• Compare 2 upwelling sites (10 lb/a/yr) vs.
• 4 not upwelling sites (5 lb/a/yr)
UMass Cranberry Station 17

18. Direction of flow
 Diversion
• Tail water recovery
 Can also relate to attenuation
 Research on how to limit flow-through
situations – by-pass canals?
• Compare flow-through (8.6 lb/a/yr)
• To all other types (6.4 lb/a/yr)
UMass Cranberry Station 18

19. Pathway of flow
 Attenuation function of ponds, steams, and
wetlands
 Mill Brook watershed (Howes and Millham, 1991)
• TDN leaving the bog was 0.99 ppm
• Downstream the load had decreased to 0.71 ppm
 Vegetative channels or retention ponds between
the bog and the final discharge point – how to
best accomplish this?
UMass Cranberry Station 19

20. Literature review - attenuation
 Denitrification in wetlands is effective at
attenuating N
• NO3 to N2
 Denitrification in ponds and streams
• Ponds – 50% attenuation
• 2 studies: 39-95% and 84-96%
• Streams – 30% attenuation
• 30-40% observed in riverine systems
 Uptake by vegetation less effective
UMass Cranberry Station 20

21. UMass Cranberry Station 21