Table 11. Phosphate (P2O5) and potash (K2O) recommendations for barley, oats, canola, wheat, rye, millet, buckwheat, grass pasture and brassicas grown on mineral soils.

Crop

Yield goal, bu/acre

Soil
Test

Barley
Oats
Canola
Wheat

401
60
-
-

60
90
-
-

80
120
40
50

-
-
60
70

-
-
80
90

lb P/acre

lb P2O5/acre2

10
20
30
40
50
60
70
80
90
100

50
40
20
0
0
0
0
0
0
0

70
60
50
30
20
0
0
0
0
0

100
80
70
60
50
30
20
0
0
0

120
100
90
80
70
50
40
30
20
0

140
130
110
100
90
80
60
50
40
30

lb K/acre

Potash recommendations for sandy loams and loamy sands
lb K2O/acre2

50
75
100
125
150
175
200
225
250
275
300
325

70
60
50
40
20
0
0
0
0
0
0
0

100
80
70
60
50
30
20
0
0
0
0
0

120
110
100
80
70
60
50
30
20
0
0
0

140
130
120
100
90
80
70
50
40
30
20
0

160
150
140
130
110
100
90
80
60
50
40
30

lb K/acre

Potash recommendations for loams, clay loams and clays
lb K2O/acre2

50
75
100
125
150
175
200
225
250
275
300
325
350

110
90
70
50
30
0
0
0
0
0
0
0
0

140
120
100
90
70
50
30
0
0
0
0
0
0

180
160
140
120
100
90
70
50
30
0
0
0
0

210
190
170
160
140
120
100
80
60
40
20
0
0

250
230
210
190
170
150
130
120
100
80
60
40
20

1Recommendations in this column apply to rye, buckwheat, millet, grass pasture and brassica species grown for forage. 2Recommendations are calculated from the following equations and rounded to the nearest 10 pounds:

XP = A + B * YG - C * ST
XKs = A + B * YG - C * ST
XKc = A + B * YG - C * ST

where:

XP = lb P2O5/acre
XKs = lb K2O/acre sandy loams and loamy sands
XKc = lb K2O/acre loams, clay loams and clays
YG = Yield goal, bu/acre
ST = Soil test, lb/acre

and the coefficients are:

XP

XKs

XKc

A

B

C

A

B

C

A

B

C

Barley
Canola
Oats

16
65
8
53

1.15
1.09
1.83
1.09

1.25
1.25
1.25
1.25

52
102
46
90

1.15
1.09
0.83
1.09

0.50
0.50
0.50
0.50

74
145
67
135

1.75
1.73
1.25
1.63

0.75
0.75
0.75
0.75