Frost forces reseeding

Some western Canadian growers have re-seeded their canola crops because frost hit almost all of Manitoba and most areas of Saskatchewan in late May.

However, the damage was not widespread because canola plants were just beginning to pop out of the soil.

Justine Cornelsen, Canola Council of Canada agronomist in Manitoba, checked a few canola fields in the western part of the province after the frost.

She did see plants with burned cotyledons, but the fields she looked at were salvageable.

“The growing point (was) still green (on many plants),” she said. “That’s a good sign. That’s all you really need is for that hypocotyl tissue (central growing point) to be green.

“That means it’s going to hopefully push through a true leaf…. If that tissue survived and is green and vibrant, it means that plant should pull through.”

Manitoba Agriculture weather data, from the morning of May 27, indicated that temperatures dipped below zero in every agricultural zone of the province.

Many areas had temps of -1 C to -2 C, but temperatures in northwestern Manitoba and the northern Interlake were more extreme. In those regions, the thermometer sank below zero for six or seven hours, with minimum temperatures hitting -3 C to -4 C.

Arborg, for example, recorded six hours of below zero temperatures, with a minimum temp of -3.1 C while Grandview had eight hours of below zero temperatures with a minimum of -4.6 C.

“Minus four for four to six hours is a fairly heavy frost for a significant amount of time,” said Anastasia Kubinec, Manitoba Agriculture manager of crop industry development.

The story is similar in Saskatchewan. There were geographic pockets where the temperature sank to -3 C and lower.

Southeastern Saskatchewan suffered the coldest temperatures.

Todd Lewis, president of Agricultural Producers Association of Saskatchewan, said growers in the region spent last week assessing the damage. Some chose to re-seed and others did not.

With frost, it’s all about timing. The majority of canola acres were seeded after May 15 and soil temperatures were cool this spring.

So, for many growers, the May 27 frost arrived before canola plants had emerged, or just as canola plants were popping out of the ground.

As well, it seems like soybeans survived the frost in Manitoba.

Most soybean plants had not emerged or were just out of the soil when the frost hit, said Serena Klippenstein, Manitoba Pulse and Soybean Growers production specialist.

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