Sunshine, warmer weather should reveal any frost damage
WORTHINGTON -- It's been several days since the thermometer dipped below 32 degrees, but the lack of sunshine and warmer weather still has many crop producers wondering about the extent of frost damage to their emerged corn fields.
Mike Crowley, an AgStar Crop Insurance agent in Worthington, said he's talked with a lot of concerned farmers since Monday about the potential yield impact from the several hours of below-freezing temperatures in the region early Sunday morning.
"The biggest thing is we need some heat and some sunshine before we can see if there is damage," Crowley said. "I think we're going to be OK. We may see some damage out there, but I think it will be very minimal."
Crowley said most of the corn in this area is between the V-2 and V-3 stage of development, with some at the V-4 stage. The growing point doesn't emerge from the soil until about the V-5 or V-6 stage of crop development, leading farmers to wonder just how the below-freezing temperatures affected the crop.
"It's got to get cold for several hours before that growing point is damaged," said Liz Stahl, crops specialist with the University of Minnesota Extension Regional Center in Worthington.
While farmers may see that some of the leaf tissue was frosted off, Stahl said they will need to check their corn stands and dig up some plants to determine the severity of the damage.
"The growing point should be white and kind of firm," she said. "If it's brown and mushy -- even orangey -- it's likely not going to make it.
"If it's white and firm, that's good," she added. "Some sun and heat will get that plant recovered."
Stahl said farmers should wait three to five days after the frost event to see if the plants will recover, but with the cool and wet weather this week, it may take more time to see signs of damage.
"By Friday and Saturday -- once we have some sun -- that will be a good time to see if plants are recovering," she said. "(Corn plants) can lose a lot of leaf tissue and come back, as long as that growing point's healthy."
Crowley said it's too early for anyone to talk about replanting, and he doesn't think the frost was severe enough to force producers to do so.
"I think we just need to show a little patience," he said. "When we get warmer weather, that's going to dictate what we see. Sunshine and warm weather -- that's the best medicine we can ask for."
Stahl said producers will need to weigh their options.
"If you have some low areas, frost damage will be worse there," she said. "You have to look at the planting date and your yield potential and the cost to replant and weigh that against the stand."
As for other crops, Stahl said most of the soybeans that were planted have not yet emerged. Seed should not be damaged by the frost, though the longer they sit in a cool, wet soil, the more susceptible they become to disease.
"Anybody with new seeded alfalfa should check that also," added Crowley. "It needs sunshine and it needs heat."
According to the Minnesota Field Office of the National Agriculture Statistics Service Crop-Weather Report issued Monday, 94 percent of the state's corn crop has been planted, with 32 percent emerged. Approximately 40 percent of the state's soybean crop is in the ground, with 1 percent emerged.