Better Farming - August 2016

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38 Farm News First > Better Farming August 2016
CROPS:YIELDMATTER$
by DALE COWAN
We cannot control the weath-
er. If it rains, it rains; if it is
cold, it’s cold; and if it is
hot, it’s hot. Currently, Environment
Canada offers us a wide view of what
has happened in a region. In agricul-
ture we farm by the field, or at least
we should. We all know that weather
greatly influences all aspects of life.
If your farms are some distance
apart, then knowing the rainfall
differences could be of greater value.
Precipitation from across our trading
area from May 1 to May 31 shows we
have accumulated rainfall ranging
from 14 mm to 65 mm. We can see
differences in as little as two
kilometres of between five mm and
20 mm of rainfall. The recording of
planting dates, along with accumulat-
ed weather and use of crop growth
models, can be used to predict the
rate of crop development in each
field.
As an example, April 27-planted
corn emerged on May 14, will reach
the end of the critical weed-free
period on or around June 1, reach V8
on or around June 17, and VT stage
on or around the week of July 11,
and black layer around September
17. It will lose 12 per cent moisture
by or around October 17 to be at 18
to 23 per cent harvest moisture.
There are at least six significant
management milestones on crop
development here to be considered
ahead of time. All are based on
planting date and CHU (crop heat
unit) accumulation.
I know some are chuckling because
you cannot predict the weather. I will
argue back that growth stages are
predictable more than you realize,
and as long as you have appropriate
details of weather at field scale you
can arrive at a prediction plus or
minus a few days on growth stages. It
is not a mystery! It took nearly 15
days for corn to emerge because it
needs 180 CHU. It took 14 to 17 days
Why track the weather on my fields?
Although we might not be able to control the weather, combining weather data with
other information about our crops can help us determine the right field management decisions
throughout the growing season.
GETTY