Alberta’s weird winter weather conditions didn’t seem to wreck winter wheat crops across the province, says a local winter wheat agronomist.
“From our spring assessment, the majority of the fields has very little damage, even with the unusual winter conditions we experienced across the Prairies,” said Janine Paly of Ducks Unlimited Canada.
The Ducks Unlimited agronomy team conducted a cross-country check of winter wheat fields throughout March — earlier than normal — because so many producers were worried, said Paly.
“This is a very early spring assessment, but we’ve had many inquiries on winter survival from growers and industry. We thought it would be useful to know how the winter wheat crop fared.”
A number of “compounding factors” affect winter wheat survival, she said. While some varieties are hardier than others, plant stage is what counts.
“A well-established plant at the three-leaf stage in the fall has a better chance of surviving the winter than a plant at the one-leaf stage,” said Paly. “The well-established plant has had more time in the fall to develop a healthy crown than the one-leaf plant.
“The crown of the plant is its lifeline. If the crown is damaged, the risk of injury is greater.”
Adequate snow cover reduces the risk of injury.
“Winter wheat reaches its max hardiness early winter, which correlates with cold winter temperatures,” said Paly.
“At that point, snow cover is ideal as it protects the plant from the harsh elements of winter, but in some regions this January, the snow melted, exposing the plant to the environment.”
Even so, soil temperatures at the crown have to reach “a very low temperature for injury to occur,” she said.
And by all accounts, that didn’t happen.
Using the Winter Cereal Survival Model, a tool developed by the University of Saskatchewan, the Ducks Unlimited agronomists found the temperature at crown level didn’t dip below “a critical point for severe damage to occur.”
Wait to assess
January’s warm temperatures also had producers asking if their plants have dehardened, or come out of dormancy. The answer to that is “most likely not.”
“Wet, frozen grounds warm up slowly, and it may take several weeks of warm air temperatures for the ground at the crown level to reach a certain temperature in order for the plant to deharden,” said Paly.
“Where we might see more damage occur is where snow melted and ice formed in the low-lying regions of the field.”
And though producers may be tempted to get out in their fields to check on the crop, they should start scouting in early May and conduct a “proper assessment” midway through spring seeding, she said.
“This allows for the crop to recover but also time for the producer to decide if he should keep the crop or terminate,” said Paly.
Producers should be targeting a plant population of between 20 to 30 plants, but crops with lower plant populations — between 10 and 15 plants per square foot — can still be profitable, she said.
“Winter wheat has the ability to tiller and to make up yield lost due to a decrease in plant stand, but the crop will then act similar to a spring wheat crop, with later maturity and less competitiveness against weeds,” said Paly.
“The grower will have to manage the field differently.”
Top dressing nitrogen “as early in the spring as possible” will help the crop get off to a good start, especially if the plants aren’t doing well.
“If a producer decides to keep a struggling crop, an application of a wild oat herbicide may also be warranted, since the winter wheat crop will not be as competitive.”
Producers conducting an early assessment should dig up some plants, wash off the dirt, and place them in a wet paper towel in the sun.
“Within two or three days, the grower should see new roots develop. If in six days there is no root development or top growth, the plant did not survive.”
During an in-field assessment, producers should dig up the plant and examine the crown tissue — not the leaves.
“Brown leaves may not be a sign of a dead plant. The only way to be sure is to examine the crown region,” she said. “A white crown means the plant survived and brown indicates it did not.”
But for the moment, Paly’s advice to growers is to “be patient and give the plant time to recover.
“This winter was particularly harsh, and the plants may require more time to recover than a normal year.”