Juliet Marshall said she’s received calls from concerned growers from Aberdeen through Idaho Falls about how consecutive mornings of freezing temperatures from June 16-18 may have affected winter wheat kernels.
Marshall said she’s seen a field of Timothy grass west of Aberdeen that sustained frost damage, and winter barley in Magic Valley also likely sustained damage.
“We are concerned about the winter wheat, and potentially some of the more advanced spring wheat,” Marshall said, adding grain fields in higher elevations are especially vulnerable.
Marshall explained wheat is susceptible to frost damage between the boot stage — when the head of the plant begins to form under the flag leaf — and the emergence of the wheat head. Marshall said it should become apparent within the next two weeks whether or not growers have good grain sets.
“I think we’re right in a bad spot for some of the earliest maturing varieties,” Marshall said.
During recent visits to growers’ fields, Marshall has seen bleached and dead auns, which are the beards of wheat and barley plants that emerge first and are often a good predictor of frost damage.
“The frost has damaged some of the crops. We’ve seen some tip burns on the auns,” Marshall said.
Marshall said frost damage may also have killed the anthers of wheat heads. Wheat and barley heads are mostly self pollinated. Dead anthers could result in a “blanking of heads,” she explained. Reduced seed set could also increase the likelihood of certain diseases surfacing in grain, such as Fusarium head blight, she said.
“I do think we’ve gotten cold enough to have significant damage, but nowhere near 100 percent,” Marshall said.
Researchers at UI’s Aberdeen Research & Extension Center reported having 13 days of temperatures below 38 degrees between May 1 and June 20, compared with nine last season.