TWIN FALLS - It's not the amount of rain, it's the timing of that rain, that can cause an unharvested grain field to be downgraded from high quality to feed quality or less.
For many grain producers in the Magic Valley and eastern Idaho, the timing of these August rains couldn't be worse.
"It's bad," said Juliet Marshall, University of Idaho extension grain agronomist and pathologist in Idaho Falls. Much of the 2014 crop that hadn't been harvested before the first drops fell is now a total loss. Only 60 percent of the state's winter wheat and one-fifth spring wheat and barley crops had been harvested according to the National Agricultural Statistics Service.
Ripe grain kernels -- both barley and wheat -- have dried down to a point where they can be stored and planted the following year. But once water is added to that mature plant, the seed coat begins to swell and the embryo inside the kernel begins the process of germination. Starch that has been stored in the kernel is converted into a form that the developing seedling can use to grow.
Unfortunately, it's not a form of starch that bakers or brewers can use. Dough made from hard red winter wheat that has sprout damage, for example, is "gummy" and the resulting loaves are not acceptable.
Once that process of sprouting begins, it cannot be reversed, Marshall said. "It's a total loss unless you can market it for feed," she said.
And that's not a guarantee. Sprouted grain is one thing, but livestock producers will not feed moldy grain. If rains do not stop soon so that the heads can dry out, kernels will begin to mold and livestock won't eat it.
"That's the question now, can you get it harvested before it becomes moldy?" Marshall said.
She recommends harvesting around any areas of lodged grain in fields. Those areas will have the greatest potential for mold or sprout damage as the heads were in close contact with the wet ground.
Also, sprouted grain will disrupt moisture sensors on combines. Growers should expect grain to be a full percentage point wetter than their sensors indicate. "If you can bin it for feed, make sure your moisture reading is in the safer zone and isn't on the margin," she said. Storing sprouted grain that is too wet will quickly lead to hot spots and mold in the bin.
She is also concerned about volunteer grain germinating this fall and serving as a green bridge for insect-vectored diseases such as yellow dwarf barley virus.
Many grain growers irrigate wheat or barley stubble to germinate the kernels that come out the back of a combine during harvest, then disk that regrowth under in the fall. But all this rain will encourage rapid germination at the same time growers are struggling to cope with delayed harvest.
Growers will also need to pay close attention to their seed source this fall and again in the spring. Some of the better quality sprouted fields have 10 to 30 percent sprout damage; that means those kernels have a potential of only 70 to 80 percent germination after planting, at best.
"That's some of the better quality stuff," Marshall said. She will be require cooperators in her 2014-15 variety trials to source their seed outside of southern Idaho to ensure adequate stands. "Be very cognizant about where your seed is coming from and what the germination rates are."
Spring grain planted in high elevation production area, such as above Ashton, that had not reached physiological maturity before the rains began may yet make quality standards. Growers won't know the extent of damage to those fields for another week or so.
"There may still be areas that make good quality wheat," Marshall said.
While she is pessimistic about the condition of unharvested grain, Marshall can find one bright spot in all this rain -- dryland winter wheat growers will seed this fall into some of the best soil moisture they have had in years.
"Next year's winter wheat crop crop will get off to a very good start," she said.