Frost, snow and a cool May combined to set back crops on the Prairies, forcing some farmers to reseed and others to switch to early maturing varieties.
Kerry Ogilvie awoke several times during the early morning hours of May 25 to find -2 C temperatures that had frosted his vehicles and flattened weeds in his farmyard near Pense, Sask.
“It was frosty by 5 (a.m.),” he said.
The first-time canola grower said his newly emerged crop looked “really hurt” that first morning but has since started to recover. He has staked the harder hit areas to check plants over the coming days.
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“If I had to reseed canola, it would be quite a cost,” Ogilvie said, citing the high price of seed and fertilizer.
He expected the frost to claim up to 15 percent of the half section of canola he started planting May 6.
While his region generally sees frost as late as May 21, this one was different, he said.
“It was a real hard frost, a harder frost than normal,” said Ogilvie.
Cool, wet spring conditions delayed seeding in Alberta, with High Prairie and Valleyview producers just able to get into the fields last week.
The south, typically the most advanced in seeding progress in Alberta, is as much as two weeks late.
“Seeding in places is way behind,” said Rod Scarlett, executive director of Wild Rose Agricultural Producers.
Emerging crops have been slow to develop in single digit temperatures and many producers are switching to earlier maturing barley on their remaining acres, he said.
Up to 13 centimetres of snow fell along the Edmonton and Calgary corridor last week with almost all of Alberta touched by flurries.
Scarlett figured emerging crops would probably fare better covered by snow than touched by frost.
Interviewed May 28, he was unsure how much reseeding would be needed due to frost as farmers were continuing to assess the damage.
He looked forward to the promise of warmer temperatures this week.
“Things will grow real quick and show (damage) real quick,” he said.
Cool temperatures and rain showers made for less than ideal conditions in Manitoba. Frosts of -5 C were reported at Ashern and -3 C at Swan River last week, with damage reported to early seeded plants and to crops like canola, alfalfa and peas.
“Heavy rainshowers between Boissevain and Killarney bringing five inches of rain may cause more damage than the frost,” said Boissevain producer Duane Edwards.
His area got similar downpours but was previously dry.
“It was about right. The water was not laying around, but soaking in well,” said Edwards, who hoped the moisture would provide a good start for crops in the ground.
He said peas that “jumped out of the ground” in the warmer days of April have since slowed down.
Edwards, who also planted wheat, oats, barley and canola, said his crops took more than a week to emerge during the cooler days and nights.
“A lot of the guys’ crops have emerged and are at a pretty tender stage,” he said.
In a Canola Council of Canada release, agronomist Doug Moisey said canola plant recovery in cool weather is slow, but worth the wait.
With warmer weather, green regrowth from the growing point should occur in four to five days. Under cold or dry growing conditions, regrowth can take up to 10 days.
“If there is any green colour at the growing point in the centre of the frozen leaf rosettes, the majority of the plants should recover and yields will be higher than if the field is worked and reseeded,” he said.
A light frost that wilts the leaves or causes yellowing or whitening without any browning means minimal injury to the plants.
To evaluate a frost-damaged field, Moisey said growers should walk a diagonal path across the field, stopping every 20 paces to evaluate all plants in one quarter of a sq. metre. He advised not to reseed if 80 percent of the field has a minimum of 20 to 40 recovering healthy plants per sq. metre.
In 2004, a canola council case study of reseeding canola after frost showed a yield loss of 7.4 bushels per acre compared to leaving the frosted crop.
