Developing US corn, soy could face yield losses
The delayed development of US corn and soy crops could entail potential yield losses further down the road if temperatures spike and rainfall ceases in top-producing states.
Corn, lagging developmentally by one to four weeks across the US corn belt, is set to enter a phase of growth generally considered the most critical to yield determination.
Using history as a guide, late starts are really, really rough on yields, said Elaine Kub, grains analyst for Nebraska-based Data Transmission Network (DTN).
In the top-producing states, corn is just now entering the so-called silking phase of development, widely regarded by crop physiologists as the most critical time for yield determination.
Normally, this phase begins in late June when weather conditions are traditionally cooler. This year, though, an unseasonably cool, wet April in the US corn belt was followed by excessive rainfall and flooding in early June, forcing delayed planting and above-average replanting.
There is heightened risk this year, and now we are at that time where it plays out, said Bill Nelson, grains analyst with Wachovia Securities.
At this point, weather patterns in the Midwest are remaining favorable, Nelson said.
The USDA said Sunday (July 14) 6 percent of the US corn crop was silking, behind the five-year average of 19 percent.
In both Indiana and Iowa, none of the corn was silking, compared to the averages of 5 percent and 20 percent, respectively. Only 1 percent of Illinois corn was silking, behind the average of 36 percent
The forecast for average US corn yields was lowered Friday (July 11) to 148.4 bushels per acre in the USDA's monthly supply and demand report. In June, the USDA was predicting 148.9 bushels per acre.
A lot of yield loss potential is going to depend on what conditions we have in the next couple of weeks, said Ron Litterer, president of the National Corn Growers Association.
In both Illinois and Iowa, agronomists are keeping an especially close eye on future weather patterns.
Meanwhile, soy is less of a concern at this point because of the crop's resilience in the face of higher temperatures and abnormal dryness.
They can really withstand the dry heat of the summer, said Kub.
The USDA said 12 percent of the US soy crop has bloomed as of Sunday, below the five-year average of 26 percent.
In Iowa, 15 percent of the crop was blooming, while the bloom rate in Illinois was 11 percent. These are both below the averages of 32 percent and 31 percent, respectively.
Although there is a heightened risk of soy flowering during weather conditions conducive to yield loss, the soy crop is in no immediate danger, said Palle Pedersen, soy extension agronomist at Iowa State University.