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Another trial was planted late but the narrow
row effect was much smaller here (data not
shown). Early frost interrupted the growing
season of the longer season cultivars in that
experiment which confounded the results.
Conclusions
Only one year’s data is available for the
Vrede CA study area in Ascent, but the re-
sults are very promising. It was shown that
one of the beneficial effects of cover crops
under no-till is an increased water infiltra-
tion rate.
The general belief that winter cover crops
are not suitable for this area was shown to
be invalid. The soils of this particular area
are shallow with a high clay content and it
seems as if tillage practices leaving the soil
bare will dry the soil to the same extent
that a cover crop will, but without the ad-
ditional positive effects on soil health and
infiltration.
The data suggests that better infiltration
rates and timely rains during the following
growing season will alleviate any initial dry-
ness effects that winter cover crops might
cause. No-till plots had generally higher
yields than other practices, but longer term
data will be needed to confirm this finding.
Neither positive nor negative row width ef-
fects on maize yield could be shown with
certainty, but there was a definite positive
narrow row effect on soybean yield. Nar-
row rows were expected to favour soybean
yields for this year because plants were
stunted by early season drought. It is possi-
ble that yields might not be better in narrow
rows during a high rainfall year, but even
then it should still be beneficial in terms of
better distribution of roots and increased
water infiltration for follow-up crops in the
no-till system.
The impact of CA should be viewed holis-
tically and over the long term. Economic
analyses will be conducted by VKB, which
is important to persuade producers. Fur-
thermore, several soil health parameters
are also monitored, since it is the basis
for the success and improvement of these
mixed farming systems over the long term.
These results will be presented in following
articles.
2b