waiting a bit later, until after the middle of
May, produced the best results.”
O’Donovan attributed that simply to
cooler growing conditions in the Peace
region earlier in the year.
“For most of the Prairies, except for
the Peace region, earlier seeding of malt
barley produced higher yields, improved
quality characteristics and lower protein,”
he said. “With later seedings, the protein
increased.”
OATS ARE SPECIAL
Oats require a heavier seeding rate than
either wheat or barley, according to
Bill May, an AAFC researcher at Indian
Head, SK.
Extensive research has shown
producers should target a minimum of
300 live plants per square metre (about
30 per square foot) to produce an
optimal, high-yielding stand that matures
evenly and competes against weeds.
“Oats have more variability than any
other cereal crop we grow,” said May.
“So to determine the proper seeding
rate it is really important to determine
the weight of your oat seed batch using
the 1,000-kernel weight formula. And
we have found there is more difference
between seed lots than there is between
cultivars. So you just can’t say that,
because you grow a certain variety, the
seeding rate should be this amount.
You need to calculate that 1,000-kernel
weight for each seed lot.”
Comparing it to a bushel measure to
achieve 300 live plants per square metre
(three square feet), May has seen bushel
measures vary from 2.2 to four bushels
per acre, depending on the seed batch.
May said a live plant stand of about 30
plants per square foot produces even
maturity for farmers planning to straight
combine the crop. And that stand
density provides fairly good suppression
of what he described as “a light wild oat
infestation.”
He explained that, if producers are
facing a heavy wild oat infestation, they
need to bump the seeding rate to 350 to
375 live plants per square metre (about
35 to 38 plants per square foot).
“When it comes to controlling wild
oats in oats, seeding rate is about the
only option farmers have,” he said. “They
need to establish a proper plant stand to
compete against the weed. There is no
real adverse affect in going to the higher
seeding rate other than increasing the
cost of seed.
“If farmers have a lower plant count
with oats, they are really going to lose
ground against wild oats. That 300
to 350 live plant count is really quite
effective at knocking back wild oats.”
According to May, an earlier seeding
date is better than a later seeding date—
both in terms of yield and crop quality.
“It depends what the producer is after,
but if they are looking for a high-yielding,
milling-quality oat with a higher test
weight, an earlier seeding date is best. It
is best to seed oats in the first half of May
rather than in late May or early June.”
He said research shows as much as a 50
per cent yield loss between oats seeded
in mid-June versus oats seeded in mid-
May, and test weight drops significantly
with the June seeding, as well.
“And that recommendation will vary,
too, depending on what part of the
province or Prairies you are seeding in,”
said May. “The test weight increases
as you seed from south to north. Test
weights are going to be higher in areas
with cooler, moister growing conditions.
For example, and I emphasize this is
usually the case, if you seeded oats on
the same day at Indian Head and then
100 miles north at Ituna, the oats at
Ituna would have a higher test weight
because of the ‘usual’ cooler growing
conditions.”
May said another way to look at it for
farmers in the southern Prairies is that
it’s best to seed oats in early May to
protect test weight because of the usual
hot, dry conditions during the growing
season, whereas farmers in central and
northern areas could probably seed oats
the second or third week of May and still
achieve very good test weights.
Spring
2015
grainswest.com
35
oPtiMuM:
An ideal stand of AC Metcalfe malt barley. As part of John
O’Donovan’s work, it was seeded at a rate of 300 seeds per square metre
(three square feet), with about a 70 per cent emergence rate producing 22
to 23 plants per square foot. Photo courtesy of John O'Donovan.
