Loss Calculation
“Quick check” for combine grain loss
Spreading discharge
Grain loss calculated per square foot across the entire field.
To perform a quick estimate for total grain loss from the combine, count
the number of seeds found in a square foot behind the combine. Determine
the quantity of loss in at least three places throughout the field to arrive at
an average.
•
Remember to subtract any pre-harvest loss, grain loss caused by the
header, or loss due to combine leaks in the field!
Use
TABLE 1
below to determine grain loss in bushels per acre.
TABLE 1 - SEED COUNT PER SQUARE FOOT
15 ft.
20 ft.
25 ft.
30 ft.
35 ft.
40 ft.
Wheat
19
19
19
19
19
19
Corn
2
2
2
2
2
2
Soybeans
5
5
5
5
5
5
Canola
111
111
111
111
111
111
“Next step” for combine grain loss
If it is determined in the “quick check” that combine harvest loss is
unacceptable, it is critical to determine the quantity of loss due to the rotor and
the quantity due to the shoe.
Follow the steps below to estimate grain loss from the rotor and the shoe.
TABLE 2 - CALCULATED LOSS IN TOTAL GRAIN PER SWATH
15 ft.
20 ft.
25 ft.
30 ft.
35 ft.
40 ft.
Wheat
285
380
475
570
665
760
Corn
30
40
50
60
70
80
Soybeans
75
100
125
150
175
200
Canola
†
1665
2230
2775
3330
3885
4440
Canola by
Weight (g)
7.8
10.4
13.0
15.6
18.2
20.8
Canola by
Volume (mL)
18
24
30
36
42
48
† Canola shown in weight and volume due to the large quantity of seeds
required to equal 1 bushel of loss.
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