Better Farming - November 2016

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48 FarmNews First > Better Farming November 2016
The set of the disc makes a difference.
A more aggressive angle leaves less
residue. The hybrid makes a differ-
ence. (Some hybrids produce more
residue than others; some break down
easier and some have more lignin.)
Whether you chop stalks or not
makes a difference. Generally, if you
chop the stalks there is less residue.
The soil type also makes a difference.
Be sure to experiment and see how
much residue you have left. Remem-
ber you want a minimum of 30 per
cent residue cover. To ensure your
calculations are accurate, you should
measure residue in a number of
places across the field.
If you chop stalks, you should do
some type of conservation tillage. If
you do not engage in such tillage,
then there will be a thick mat on the
soil surface next spring. This mat will
lead to a wetter, colder soil than if you
did not chop the stalks.
One question that was asked was,
what if I have some knolls that tend
to erode? Will 30 per cent residue
cover be sufficient? Probably not. If
this is your situation, then do not
practice conservation tillage on the
knolls.
Lift the equipment when you get to
the knolls or go around them. This
practice will help reduce soil erosion
and give the neighbours something
else to talk about. BF
Consulting agronomist Patrick Lynch,
CCA (ON), formerly worked with the
Ontario agriculture ministry and with
Cargill.
CROPS: THELYNCH FILE
A variety of factors affect the amount
of residue left on the soil, including
the depth and speed of the tillage tool.
In this plot, there was almost
30 per cent residue cover.