The Farmers Mart Oct-Nov 2018 - Issue 59 | Page 46

46 GETTING READY FOR WINTER
OCT/NOV 2018 • farmers-mart.co.uk
FIVE-POINT PLAN OFFERS GUIDANCE FOR
DELAYING AUTUMN WHEAT DRILLING
Think before rushing in to drill winter wheat after the early harvest and now we’ve had rainfall, farmers are being urged.
WITH large areas of land harvested much
earlier than normal, and soil moisture levels
improved, growers will be itching to drill
empty fields, says Nick Myers, head of crop
production for agronomy firm, ProCam. But
on farms suffering from blackgrass, there’s
a compelling argument for holding back, he
stresses.
“Low blackgrass seed dormancy after
the hot, dry summer might increase the
temptation to bring drilling dates forward –
because a bigger proportion of this year’s
shed blackgrass seed is predicted to germi-
nate earlier. But resist that temptation,” Mr
Myers urges.
“The later you can safely delay drilling,
the less blackgrass you’ll have emerging in
the crop, and the less blackgrass seed will
potentially be shed back to the soil next
summer.
“Instead of viewing this as an opportunity
to drill earlier, think of it as an opportunity
to make worthwhile inroads into reducing
blackgrass populations for the long-term.”
On farms where delayed drilling has
already been practiced for a few years, and
blackgrass levels have already started to
decline, Mr Myers acknowledges it might be
particularly tempting to edge drilling earlier
again this year. But, he says, this could undo
some of that good work. “Some blackgrass
will inevitably germinate later anyway,” he
adds.
“Obviously, you have to assess how late
you can drill based on your farm situation.
If you can’t delay all fields, at least delay
those with the highest weed burdens.”
To help growers navigate through
delayed autumn wheat drilling in black-
grass fields, Mr Myers suggests a five-point
plant:
1. Leave stubbles undisturbed as
long as possible. That way you’ll
allow longer for blackgrass seed on the
surface to germinate, but also longer
for it to be eaten by predators. Only
disturb the soil at the point of having to
prepare the seedbed.
2. Avoid using inversion tillage
(ploughing) if possible. The longer
you can leave buried blackgrass seed
underground, the more of it will rot
away.
3. Prepare high quality seedbeds.
These will stimulate the maximum
amount of blackgrass to germinate
before planting the crop. That way,
even more blackgrass can be killed off
in a stale seedbed. Good seedbeds will
also produce better performance from
soil-acting herbicides, he notes.
4. Depending on farm situation,
consider delaying drilling until
well into October. October-drilled
wheat generally contains much less
blackgrass than September-drilled.
Also, information from ProCam’s 4Cast
crop database showed winter wheat
yield hadn’t declined despite average
drilling date being delayed from 2 Octo-
ber to 12 October between the harvest
seasons of 2011 and 2017. Most likely
this was because any yield penalty
from later drilling was offset by crops
containing less blackgrass.
5. Adapt agronomy according to
later drilling. Select wheat varieties
that can compensate for later drilling
through greater tillering, and that are
flexible with regard to drilling date. The
variety might be 1 or 2% lower yielding
on paper, but you could end up with a
better crop. Also, take steps to maxim-
ise establishment, for example by using
a seed treatment shown to produce
rapid establishment.
‘ The later you can
delay drilling, the less
blackgrass you’ll have
emerging in the crop
’
“As well as helping against blackgrass,
delaying drilling can also help against
ryegrass, and help to reduce take-all,
eyespot and lodging pressures in winter
wheat,” says Mr Myers. “It can also help
reduce the risk of BYDV because there are
likely to be fewer aphids about.
“Moister soils with later drilling will also
improve the uptake of residual herbicides
by weeds, while colder soils will mean
residual herbicides are broken down more
slowly, so they last longer.
“That said, do balance delayed drilling
with allowing enough time to prepare the
land and enough time for post-planting ac-
tivities, such as spraying,” he adds, “before
the weather closes in.”
www.procam.co.uk