Phosphorus in Cranberry
Nutrient Management
Carolyn DeMoranville
UMass Cranberry Station
Cranberry Station
Why is this important?
Cranberry Station
2
What have we done?
• Plot scale work to define P requirement
– >0 but <22 kg
• Field-scale: Enlist growers to reduce well below
22 kg/ha (‘not to exceed’ level)
• Collect data from their farms
– Crop yield
– Tissue P
– Water quality
• Use these data to make the case for others to
adopt reduced P
Cranberry Station
3
Results of surveys conducted in January 2008 (2007 season);
January 2009 (2008 season); March 2010 (2009 season).
Management choice
2007
season
2008
N:P
P>N
36%
15%
N:P
P no more than N
34%
61%
Plan to reduce P use next
season
Reduced P use
Cranberry Station
2009
36%
51%
65%
4
Grower P reduction sites study
P rate in kg/ha
Site #
P applied
2008
P applied
2009
P applied
2010
P applied
2011
P applied
2012
1
6.6
8.4
10.0
12.3
10.9
2
8.5
9.9
8.2
11.2
8.2
3
8.2
0.7
0.9
0.8
7.5
4
8.7
4.1
10.2
4.9
6.8
5
--
8.6
5.6
8.3
16.0
6
14.1
8.5
8.4
Cranberry Station
5
Through 2012 season
25
Yield (Mg/ha)
20
15
Prior Practice
Reduced P
10
5
0
1
Cranberry Station
2
3
4
5
6
6
Production vs. P applied
35.0
Data from 2005-2011
Production Mg/ha
30.0
Site 1
25.0
Site 2
20.0
Site 3
15.0
Site 4
Site 5
10.0
Site 6
5.0
Site 7
Regression
0.0
0.0
Cranberry Station
20.0
kg/ha P
40.0
7
Tissue P % dry weight
Site
Avg.
kg/ha P
2008
1
8.3
2
2009
2010
2011
2012
0.13
0.12
0.13
0.10
8.8
0.16
0.09
0.16
0.13
3
2.7
0.13
0.15
0.11
0.15
0.11
4
7.0
0.15
0.16
0.13
0.16
0.12
5
7.5
0.14
0.11
0.12
0.13
6
10.3
0.14
0.12
Standard range = 0.1 – 0.2%
Cranberry Station
8
0.8
0.7
0.6
2009
0.5
2010
0.4
2011
0.2
0.1
0.5
0
1
2
3
4
5
Years of P reduction
2009
2010
2011
7
8
9
5
6
7
2
3
4
2
3
4
1
2
3
3
4
5
Site
1
2
3
4
5
6
0.3
6
Winter Flood
0.4
2009
TP mg/l
TP mg/l
Comparison of TP in flood
releases
Harvest Flood
0.3
2010
2011
0.2
0.1
0
1
Cranberry Station
2
3
4
5
6
9
Harvest flood P concentrations
Phosphorus in Harvest Release
1.4
1.2
TP (mg/L)
1
2009
0.8
2010
0.6
2011
2012
0.4
0.2
0
1
2
3
4
5
Site
Cranberry Station
10
Winter flood P concentrations
Phosphorus in Winter Release
0.15
TP (mg/L)
0.1
2009
2010
2011
0.05
2012
0
1
2
3
4
5
Site
Note: scale is 10x less than for harvest flood
Cranberry Station
11
Harvest flood
Net P release (lb/acre foot water)
4
3.5
3
TP (lb)
2.5
2009
2
2010
2011
1.5
2012
1
0.5
0
1
2
3
4
5
6
7
Site
1 lb = 0.45 kg
Cranberry Station
1 acre-foot = 1233 m3
12
Site 1
Applied P
Pre-2003 = 22 kg/ha
0.7
Avg. starting 2003 = 11 kg/ha
P in water (mg/l)
0.6
Harvest
discharge
0.5
Change (kg/ha released)
0.4
0.3
0.2
Harvest
Winter
Year 1
2.92
1.77
Year 7
0.48
---
Year 8
0.68
0.20
Year 9
0.51
0.19
0.1
0
2002
2004
2006
Cranberry Station
2008
2010
2012
13
Potential impact
 Site 1
 Bog is ~25 ha
 In 2003, the 2 floods (winter/harvest) contained
117 kg P
 8 years later, the floods contained 17 kg P
 85% reduction
Cranberry Station
14
Next steps
 Continue and expand monitoring study, recruit
growers to use 5 kg/ha P
 Large grant to begin to install and evaluate
methods to remove or minimize P from discharge
water – filters, other BMPs
Cranberry Station
15
Questions?
Cranberry Station
16
Cranberry Bog Total Phosphorus
CES/SMAST
Field Expt.
TP
Fertilization
TP
incoming
TP
leaving
(kg/ha/yr)
(kg/ha/yr)
(kg/ha/yr)
(kg/ha/yr)
Mean 2003-04
Bog ID
EH
TP export
(net)
11.2
22.2
18.8
0.3
4.5
4.2
1.8
8.5
6.8
1.2
3.9
2.7
0.2
5.5
5.3
2.0
3.2
1.2
ASH
19.6
23.1
39.3
1.8
3.4
1.7
Mean
22.4
1.22
4.83
3.65
PV
BEN
WS
M-K
A Flow-through Bog was found to have a higher annual
TP loss of 9.9 kg/ha/yr (Howes & Teal 1995)
Yield (Mg/ha) comparison of 4 or 6 years prior to that in 2008-2011
*2008-2010
Site
**2009-2011
P 2008-2011
(kg/ha/yr)
4 years prior
yield
6 years prior
yield
2008-2011
average
1
8.3*
17.1
23.9
2
8.8*
17.4
25.8
3
2.7
4
7.0
6
7.5**
7
Cranberry Station
10.3*
12.9
14.4
19.9
?
17.4
23.4
22.3**
18.0*
18