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SEED/
SAAD
Do your own crop estimate
Dryland:
Irrigation:
Ears or stalks per m
2
x seeds per ear
3 500
= t/ha
Ears or stalks per m
2
x seeds per ear
3 000
= t/ha
Yield estimates (for various crops) are refined regularly and financial institutions continuously conduct
research on methods for determining accurate hail damage. This research is never regarded as
completed. New fields are continuously being studied and existing procedures are tested and adapted
to keep pace with, among other things, new cultivars and changed farming techniques.
One area that is studied in depth is the determination of crop yields or crop estimates. Certain
formulae are developed and adjusted, but a thorough knowledge of, among other things, the
farming branch and region remains important in determining a crop yield.
The following information should be used only as guidelines. However, it can be useful when
producers want to estimate the potential crop yield. Keep in mind that there are many variables that
can affect the accuracy of a crop or yield estimate. The closer you come to harvest time, the more
accurate are the determinations that can be made, because the chance is smaller of major variables
occurring. One of the most critical factors is the kernel mass. It not only varies considerably from one
season to the next, but also within one season. Even after the crop is ready for harvest, factors like
ear rot and other pathogens can affect the kernel mass.
The guidelines are as follows:
1. Wheat
With wheat a good average seed count is approximately:
Dryland:
3 500 seeds/100 g.
Irrigation:
3 000 seeds/100 g.
Two general practices, sowing and planting, are described separately to determine yields.
1.1 Sowing or planting wheat in very narrow rows
1.1.1 Firstly, the number of ears or stalks per square metre (m²) is determined.
1.1.2 The average number of seeds per ear is determined by counting the seeds in a sample of
wheat ears, including small and big ears in proportion. If the seeds cannot yet be counted,
a good average count for the cultivar concerned can be used.
1.1.3 The following formula can be used to calculate the yield where wheat was sown:
1.2 Wheat planted in distinguishable rows
1.2.1
Determine the row width as follows: The distance over ten row spaces is measured, in
other words from row one to row eleven, and the distance thus obtained is divided by ten
to determine the row width.
EXAMPLE
Distance over ten row spaces = 3,5 m
Row width is 3,5 m
10
= 0,35 m
Continued on p. 26