ROCKVILLE, Md. (DTN) -- Wheat is a tough crop, but it's not invincible, Kyle Krier has learned.
On the first night temperatures plunged below freezing where he farms near Claflin, Kansas, in mid-April, he winced but knew the wheat could probably make it.
"If we could have skipped that second night and third night, we would have been OK," Krier recalled. "We still had some ground warmth left." But the cold air settled in for several more nights. At one point, Krier calculated that the night air lingered below 29 degrees Fahrenheit for more than 10 hours.
Now Krier and countless other farmers in Oklahoma and Kansas are walking through fields of winter wheat -- much of it off to a good start from plentiful fall moisture -- and counting their dead.
Extension agents and crop scientists from Oklahoma State and Kansas State Universities conducted mini crop tours over the past week and found extensive damage.
"I would guess well over 50% of the state's wheat was affected," said Kansas State University wheat and forages specialist Romulo Lollato.
Southern Plains growers face tough decisions about the future of damaged fields, and weather is unlikely to be an ally in the weeks to come. "Indications for May are for the warm and dry pattern to continue -- above-normal temperatures and below-normal precipitation," said DTN Senior Ag Meteorologist Bryce Anderson.
SORTING THROUGH DAMAGED FIELDS
Kansas' top-producing wheat counties lie within the central region of the state, where subfreezing temperatures descended on some of the most developmentally mature wheat, Lollato noted. Most wheat in that region was well into the jointing stage, where the budding head of wheat starts moving up the inside of the stem, away from the protective cover of the soil line.
"The worst damage was in central and north-central Kansas," Lollato said. "There is a lot of wheat in those regions."
John Schlessiger, who farms in the central Kansas county of Barton, said he was surprised by the wide variation in damage within fields and varieties.
"You'll walk through a field and cut 10 stems in one spot and 70% of the heads are dead," he said. "Then you'll walk another 10 feet, collect another 10 stems and 70% are perfectly healthy."
Varietal differences are very visible across the state, Schlessiger and Lollato noted, due to the differences in when varieties broke dormancy. Those that responded quickly to the warm February weather and developed rapidly this spring are showing the most damage, Lollato said.
The biggest dividing factor is planting date, however.
"Fields planted early are bigger and look better from the road, with less leaf injury," Lollato explained. But once you get out into them and start splitting stems, you're finding the majority of stems were hurt by the freeze."
Within the state's centermost counties, such as Barton and Ellsworth, Lollato and his scouts found 30% to 50% damaged primary tillers in their sampling.
Late-planted fields, which had the advantage of being further behind in development, tend to look worse due to massive leaf damage, Lollato said. "They're looking really rough, with up to 80% leaf loss and even some tiller losses -- anywhere from 20% to 50%."
This dynamic surprised Krier, who was forced to mud in half of his wheat acres in November and expected the smaller, less-developed fields to weather the freeze better.
But the combination of underdeveloped root systems and dry topsoil spelled doom for many of these fields, instead. "It took it so bad," Krier said. "Those fields are just brown."
Oklahoma wheat growers saw significant freeze damage as well, reported Amanda de Oliveira Silva, small grains Extension specialist for Oklahoma State University.
"A lot of wheat fields [in Oklahoma] were at the flowering stage when the freeze came in," she wrote in a university summary article of her colleagues' wheat tour. "Most of the damage we are seeing is death of the flower parts followed by head discoloration."
Some of the worst damage was found in central, south-central and southwest Oklahoma, she wrote. Farther north, wheat was less mature and more resilient to the cold.
In contrast, as his team moved down into the southernmost tier of Kansas counties, they found less damage, Lollato said. "There was some leaf loss, but the damage was mostly cosmetic, because the growing points looked fine," he said.
UNFAVORABLE WEATHER AND HARD DECISIONS AHEAD
Growers with damaged fields now face the decision to destroy fields to plant a spring crop or take them to harvest.
Krier estimates anywhere from 10% to 50% of his wheat was seriously injured; the picture will be clearer at the end of this week's warm weather. Schlessiger believes he has lost 40% yield potential already, but he isn't ready to zero out any fields just yet.
"We don't have any fields at this point that don't look worth taking to harvest," he said. "In two weeks, that could look different."
Rainfall and temperatures in the coming weeks will be key to the recovery of damaged wheat plants that aren't fully dead, Lollato agreed. Damage estimates don't usually translate directly to yield loss -- a 50% tiller loss doesn't necessarily mean a 50% yield loss, for example -- but weather will have the final say.
"In some ways, it's easier if the whole field is dead," he observed. "In fields where 60% to 70% of tillers survived, farmers have some tough decisions. With good moisture, the yield might still be OK."
Secondary or tertiary tillers that were further behind in development from the damaged primary tiller can still develop under those conditions, he noted. Even stems that were severely damaged by the cold and are re-growing with a kink can theoretically recover and produce a head. Some very immature plants might actually put out new tillers entirely -- "starting from scratch," as Lollato puts it.
But the dry, warm weather in central Kansas this week isn't encouraging, Schlessiger noted.
"If we don't get some rain soon, this could get pretty ugly," he said. "I don't see secondary tillers taking over and producing a good crop without some moisture really quickly. We'll cut a lot of 20- and 30-bushel wheat if this weather pattern doesn't change."
Unfortunately, the forecast for the Southern Plains doesn't look promising, Anderson cautioned.
"I am pessimistic when it comes to weather over the Southern Plains the rest of the spring season," he reported. "The next week to 10 days offers some rain showers, but only modest precipitation totals. Before those showers, hot, dry and windy conditions will extract a lot of soil moisture and stress the wheat. That's followed by a 14-day forecast that turns dry again with below-normal precipitation."
For now, Lollato has posted a step-by-step guide to deciding whether to destroy a wheat crop and replant. You can find it here: https://webapp.agron.ksu.edu/….
See more on Kansas freeze damage from Lollato here: https://webapp.agron.ksu.edu/….
See more on Oklahoma freeze damage from de Oliveira Silva here: https://osuwheat.com/….
See more DTN coverage on the mid-April freeze in the Southern Plains here: https://www.dtnpf.com/….
Emily Unglesbee can be reached at Emily.firstname.lastname@example.org
Follow her on Twitter @Emily_Unglesbee
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