Weather Still Threatens Soybean Crop & Quality

Iowa's 2008 bean crop will have lower yield, lower oil content.

When USDA recently lowered its soybean production estimate for the 2008 U.S. soybean crop, by one percent to 2.93 billion bushels, based on an estimated 40 bushels per acre yield, Iowa State University Extension agronomist Palle Pedersen responded that those figures seem like a more accurate look at this year's soybean crop. Unfortunately, he says, there are concerns that this latest USDA estimate is still too high.

The next official estimate will be in USDA's October Crop Report, to be released October 10. Nice, warm weather this past week has been favorable for the maturity of this year's late-planted, late developing soybean crop in Iowa.

Expect smaller seed size, lower oil content

Pedersen says the size and quality of this year's crop will depend on several variables over the next few weeks, including weather. "For that reason we are monitoring the 7- and 10-day forecasts very carefully right now," he says.

"Under certain conditions, the crop could still improve," Pedersen says. "More sunshine and warm temperatures like we've had across Iowa this week will help soybeans mature. If we don't get an early frost, we may be in good shape. But if we get an early or average frost, that will cost bushels, no doubt about it."

Not only is the size of the crop an issue, but so is quality. Pedersen says one result of late planting is smaller seed size. "We expect the protein content to be higher than usual," he adds, "but oil content will be down."

Pedersen says nobody can guess just how low the oil content will go, but it will be lower than farmers have seen the last three or four years. To hear more, go to Iowa Soybean Association's Web site at and check out ISA's Production Research page. On the left side under September, click on the podcast titled, "Harvest Expectations."

When will first frost come this fall?

The first killing frost (28 degrees F) normally hits central Iowa around October 17, based on weather data averaged over the past 30 years. This last week Iowa has enjoyed warm, sunny weather good for maturing the crop. What are the chances of first killing frost occurring at the normal time or even later than normal this fall?

The odds for that to happen have improved, based on recent weather patterns and other indicators, says a prominent Iowa climatologist. "It now looks like we've got good prospects to make it to the middle of October before the first killing freeze might hit central Iowa. Even the first of November isn't out of the question," says ISU Extension climatologist Elwynn Taylor.

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.