Heatwave stresses spring wheat, boosting protein
Summer heat is causing stress in Washington’s spring wheat crop, researchers say.
In its weekly regional crop progress and condition report, the USDA National Agricultural Statistics Service reported that “winter wheat continued to look good, while spring wheat did not.”
Stress caused by heat and late planting in a shorter growing season is to blame, said Mike Pumphrey, spring wheat breeder for Washington State University.
“Planting was delayed everywhere,” he said.
Pumphrey said maturity wasn’t as important this year as it is in some years, because soil moisture was good.
“Some of our later maturing lines that I would say do poorer in a typical hot, dry summer didn’t because there was soil moisture,” he said.
Irrigated wheat is likely to be down from usual years, but “quite healthy” overall, he said. Dryland acres where planting was delayed will likely be average to below average.
Later plantings are likely to suffer more, while earlier spring wheat plantings had the chance to tiller before higher temperatures occurred, said Ryan Higginbotham, director of WSU’s cereal variety testing program.
“Heat is the enemy of spring wheat,” Higginbotham said.
Higginbotham expects statewide spring wheat yields will be down, but higher winter wheat yields will offset them.
The effect varies across the state. In trials in the Horse Heaven Hills area, spring wheat yields doubled over last year, while in Lind, Wash., trials, yields were half of last year’s, he said.
Assuming test weights and grain soundness are otherwise OK, Pumphrey said the heat stress may boost protein, which is a desirable trait in dark northern spring wheat.
The wheat class has seen price upswings due to supply problems elsewhere in the U.S., from $7.57 to $7.67 per bushel on the Portland market for 13 percent protein, and $7.83 to $8.77 per bushel for higher protein levels.
“Although the yields may be lower, we should have high-enough protein or good protein,” he said. “That’s going to help (growers), instead of getting them a discount. Now, that has to be balanced with how many bushels are harvested, of course.”
Lower protein percentages are wanted in soft white wheat, which will also see higher levels due to the heat stress. WSU’s trials have shown above-average protein levels, averaging 12.5 to 13 percent, “which is not ideal,” Pumphrey said.
Soft white wheat is priced at $5.16 to $5.60 per bushel.
Higginbotham’s not aware of any price discounts for high protein soft white wheat, but said it’s possible as harvest progresses.
“If there is no discount, there is no impact, really, to the grower, but if they start to implement a discount for high protein, they’re going to be feeling that,” he said.