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9/27/2010 - 10/3/2010

Flooded Grain and Other Harvest Issues

By Charles R. Hurburgh, Jr., Department of Agricultural and Biosystems Engineering, Roger Elmore, Department of Agronomy, and Alsion Robertson, Department of Plant Pathology

Harvest is underway and a few issues stemming from the unusual weather patterns last summer are coming up.

Flooded Grain
On September 30 the Iowa Department of Agriculture and Land Stewardship (IDALS), as the state representative for the U.S. Food and Drug Administration, issued a statement saying that grain submerged (over the grain) in flood waters was to be considered contaminated and therefore not eligible for entry into food-feed markets. Ethanol is a feed market because of the dried distillers grains with solubles (DDGS). This is the same policy that was used for grain in storage that was submerged in 2008 by the eastern Iowa floods. The logic is that, in addition to in-field mold issues (see example below), flood waters can contain many contaminants from a wide variety of sources. 

The release and accompanying public health fact sheet are posted on the Iowa Grain Quality Initiative website. Take safety precautions when knocking this corn down; do not run it through a combine or use a stalk shredder – doing so would increase  fugitive dust even more. The IDALS/FDA statement allows adjusters to consider the grain of no value in the crop insurance process. In the future, weather challenges may continue to create food safety situations; expect that grain will be considered in the same way as any other food ingredient as efforts to maintain food safety increase.

2010 Harvest Issues
Both corn and soybeans are likely to be harvested in warm weather this year. Be sure to cool the grain immediately after harvest to prevent spoilage from starting, even in the relatively drier grain this year. The dew point is a good indication of cooling potential; lately dew points have been in the 40s and 50s even with temperatures in the 70s and above. Low humidity air has good cooling potential as it evaporates water from grain. 

Soybeans are particularly at risk because we tend to think of them as safe for storage when they are harvested below 13 percent moisture, and therefore sometimes put them in non-aerated or poorly aerated storages. If unaerated storage must be used, only put cool, dry grain in there.

The plant diseases that affected corn and soybeans this year may not have a large effect on grain quality, other than seed size and fill. However, stalk rots are common and lodged corn may require early harvest even though the warm weather could produce more in-field drydown.  Again this creates the need to pay attention to grain temperatures while in storage and incorporate extra cooling cycles. In 2009, the common practice of storing moderate moisture corn without drying (up to 19 percent) did not work well because the overall corn storage quality was poor; this year the risk is warm corn starting to spoil if not cooled.

Nitrogen deficient corn  will likely have lower protein. Early indications are that soybean protein and oil will be good, approximately at the long term averages of 35 percent protein and 19 percent oil.

Reminder:  Corn from different crop years should never be mixed in storage. Instability results. With the large amount of the poorer quality 2009 corn still in storage, grain will be blended when  sold, but this should not be done before storage. Use test weight as a guide to determine which 2010 grain should be kept and which should be marketed or used quickly. Corn less than 54 lb/bu will have progressively poorer storage properties; likewise heavier corn will have better storage properties. With the large amount of damaged corn in storage from 2009, the market cannot accept more condition problems from 2010 corn.

Examples of submerged grain.



Charles Hurburgh is an agricultural and biosystems engineering professor who manages the Grain Quality Research Laboratory and the extension-based Iowa Grain Quality Initiative. He can be contacted at (515) 294-8629 or by email at Roger Elmore is a professor of agronomy with research and extension responsibilities in corn production. He can be contacted by email at or (515) 294-6655. Alison Robertson is an assistant professor of plant pathology with research and extension responsibilities in field crop diseases. Robertson may be reached at (515) 294-6708 or by email at

Important Update for Farmers that Supplied Grain to VeraSun within 90 days of Bankruptcy

by Erin Herbold, Center for Agricultural Law and Taxation

On Sept. 30, 2010, attorneys for the New-York based law firms, Kelley Drye & Warren and Silverman Acampora, notified several corn producers and their attorneys in Iowa and across the Midwest that they are withdrawing demands for preference claims against a number of producers in the VeraSun Bankruptcy proceeding. In August, these law firms sent letters to producers who received payment for corn or other services from VeraSun Energy within 90 days of the company’s filing of Ch. 11 bankruptcy. These letters notified producers that payments received within the 90-day timeframe were preference claims under the U.S. Bankruptcy Code that should be returned to the bankruptcy estate and offered to settle with producers for 80 percent of the amount paid. The law firms requested that farmers respond to their settlement offer by Sept. 30, 2010.

Correspondence from these law firms on Sept. 30, indicated that the firms have received “sufficient information” to determine that the VeraSun estate will not pursue a claim for relief against corn producers and the demands are withdrawn. The law firms indicated that they would compile and issue a list of corn producers against whom demands are withdrawn at a later date. The firms indicated that this should be relatively soon.

At this time, it appears that the law firms are still pursuing claims against normal preference defendants. It is not known whether the law firms have withdrawn their demand against cooperatives and private grain dealers.

After a preliminary reading of the situation, it is a good idea for corn producers to keep the documentation they have gathered together until they receive actual notice that they have been released from these claims. If you are a corn producer who proceeded without an attorney on this matter and sent money to these law firms, please contact us at the Center or consult with an attorney. It is not known, at this time, how the law firms will deal with producers who sent money. Staff at the Center for Agricultural Law and Taxation continue to monitor this situation and will provide updates at when they become available.


Erin Herbold is staff attorney for ISU Center for Agricultural Law and Taxation. She can be reached by calling 515-294-6365 or emailing

Marketing Year Prices Cancel ACRE Payments in Iowa

by Chad Hart and William Edwards, Department of Economics

Following the completion of the 2009/10 marketing year, the U.S. Department of Agriculture (USDA) released its final monthly price estimates for corn and soybeans.  Over the September through August marketing year the national average price for corn was $3.55 per bushel. This is $.51 less than the average price during the 2008/09 marketing year of $4.06 per bushel. For soybeans, the 2009/10 national average price was $9.60 per bushel, which is $.37 lower than the previous year’s average price of $9.97 per bushel. 

One of the key USDA commodity programs that depends on the marketing year prices is the Average Crop Revenue Election (ACRE) program. Given the price levels for 2009/10, the ACRE program will not provide revenue deficiency payments in Iowa this year for either corn or soybeans. With Iowa’s 2009 state average yields (as calculated by the Farm Service Agency) of 182 bushels per acre for corn and 50.5 bushels per acre for soybeans, 2009/10 national average prices needed to be below $3.49 per bushel for corn and $9.03 per bushel for soybeans in order to trigger ACRE payments. 

The 2009/10 prices also help set the revenue guarantees for ACRE for the 2010 crops. The ACRE guarantee price is a rolling two-year average of the national price. For 2010, the ACRE guarantee prices will be $3.81 per bushel for corn and $9.79 per bushel for soybeans.  The ACRE benchmark state yields are based on rolling Olympic 5-year averages. For Iowa in 2010, the ACRE benchmark yields are 51 bushels per acre for soybeans and 171 bushels per acre for corn.  These prices and yields imply that the Iowa ACRE revenue guarantees for the 2010 crops will be $586.36 per acre for corn and $449.36 per acre for soybeans.

Iowa grain producers still have the opportunity to enroll in the ACRE program for their 2011 and 2012 crops.

In-Field Drydown Rates and Harvest

By Roger Elmore and Lori Abendroth, Department of Agronomy

As of Sept. 27, nearly 91 percent of Iowa’s corn rates are “safe from frost” according to the USDA- NASS report  indicating the majority of the crop is physiologically mature (R6).   The crop’s development is five days ahead of normal, 68 percent mature, and dramatically outpaces the 43 percent mature recorded in 2009 for the same week. 

Drydown remains as the last major in-field growing season process after the grain reaches physiological maturity – ‘black layer.’ The grain, although still connected to the cob, is disconnected physiologically from the plant because of the abscission or black layer - no further exchange of either nutrients or water between the cob and the kernel occurs.

Although corn is harvested at higher grain moistures for silage and seed corn, ideal harvest moistures for field corn range from 15 to 20 percent and higher. Delaying harvest until corn dries to 15 to 20 percent will save considerable artificial drying costs. Yet as corn dries, hybrids and fields with poor stalk quality become increasingly susceptible to stalk lodging. Harvest efficiency decreases rapidly and harvest losses increase in fields with lodged corn.

Grain usually dries at a linear rate that varies depending on weather and other factors. For example, wet and cool weather slows drying. We’ve seen drydown rates less than 0.3 percent per day. On the other hand, warm, dry weather speeds drying; kernels can lose up to 1.0 percent moisture per day with excellent drying weather. Considering that corn at maturity has about 30 percent moisture content it could easily take two or more weeks for grain moisture to drop to 20 percent.

Early research with inbreds by Iowa State University documented drydown rates of 0.5 to 0.6 percent grain moisture loss per day when evaluated from late August (dent stage, R5) through October. Two years of research by University of Nebraska in the mid 1990s found a range from 0.60 to 0.64 percent moisture loss per day. In that study, four hybrids – including both conventional and transgenic - did not differ in their drydown rates. More recent data from University of Wisconsin matched those of the Nebraska research; grain lost about 0.66 percent moisture per day. 

Factors related to grain drydown
Bob Nielsen, Extension Agronomy at Purdue University, summarized field drydown in a recent web article . We’ll discuss some of his ideas here and make a few additions.

Air temperatures – heat units – largely drive in-field grain drydown. As fall progresses, day length shortens and temperatures drop. As this occurs grain moisture normally stabilizes around 15-20 percent.

Although weather – mainly temperature and humidity – is the main driver of grain drydown, we must also factor in hybrid characteristics, namely ear and husk characteristics. Modern hybrids characteristically have fewer husks and delayed husk senescence relative to older hybrids. Both of these contribute to faster drydown. 

Nielsen writes that if hybrids differ by a day of relative maturity, they will typically vary by about 0.5 percent grain moisture if planted on the same day. He also suggests that less husk coverage of ear tips and looser husks promote faster grain moisture loss.

In addition to ear and husk characteristics, research summarized by the late Don Duvick, who worked with both Pioneer and Iowa State University, shows that although old and new hybrids may have similar relative maturities and reach silking at the same time, newer hybrids exhibit faster drydown.

Two more things to consider
• Conditions this year in some fields have resulted in stalk rots. Severe weather may impact crop standability in these situations. Obviously, potential harvest losses increase when fields lodge. For example, a late October 1997 snow storm resulted in a 32 bu/acre loss in the Nebraska research discussed above. Consider scheduling fields for harvest based on stalk quality.

• Several years ago, widely circulated reports in the popular farm press suggested that corn dry matter decreases after R6 during drydown. Several hybrids were compared in three years with different drying environments each year. Grain weights, i.e. dry matter, were stable in all environments following maturity. Grain does not lose drymatter during in-field drydown (for more information on this, see the Reference listed below).

As grain dries in fields after reaching black layer, monitor individual fields and hybrids for grain moisture, stalk quality and ear retention. Schedule harvest based on these variables.

Regarding drymatter stability:  “Corn grain yield and kernel weight stability after black layer” on ISU corn web page.


Roger Elmore is a professor of agronomy with research and extension responsibilities in corn production. Lori Abendroth is an agronomy specialist with research and extension responsibilities in corn production. Elmore can be contacted by email at or (515) 294-6655; Abendroth can be contacted by email at or (515) 294-5692.

Corn Development and September Yield Forecast, 2010

By Roger Elmore, Department of Agronomy

The September 2010 USDA–NASS corn yield forecast remains at 179 bushels per acre (bu/acre) for Iowa – the same as the August report. If realized, 2010 will boast the third highest yield in Iowa’s history behind 2004 (181 bu/acre) and 2009 (182 bu/acre).

As we think about this possibility, remember that the USDA-NASS September forecast is mainly calculated from ear counts and ear dimensions. These measurements are then combined with ear weights from the last five years, depending on the maturity of the individual plot samples obtained in late August. If mature, ears were weighed which improves the accuracy of the forecast. The next forecast, Oct. 8, will include more ear weights providing an even more accurate representation of harvestable yields. USDA-NASS uses a complex set of statistical models to forecast grain yields. This is the best source for reliable yield forecasts.

This year’s Growing Degree Day (GDD) accumulation to date outpaced seasonal averages by 6 percent (Table 1). However, GDD accumulations between silk and dent averaged 116 percent of normal. By mid-August, 70 percent of Iowa’s corn was in or past the dough stage (R4) compared to 47 percent normal and only 25 percent for 2009 (USDA-NASS, 16 August). Accumulations since denting this year were 98 percent of normal (Table 1).

Cool temperatures since mid-August (dent stage R5) certainly resulted in slow GDD accumulations and slower crop development but with the fast pace of crop development earlier in the season, this will have minimal effect on yield. Charts on Iowa crop conditions - as well as those of other states – from the USDA-NASS Crop Progress and Condition report clearly shows the advanced pace of crop development this year.

Crop development racing from silking to dent is not necessarily positive. The rapid pace of kernel fill could reduce seed weights and yields (see Sept. 3 ICM article).  A silver lining is that the early maturity will result in faster drydown and thus lower grain drying costs (see Sept. 28 article).



Roger Elmore is a professor of agronomy with research and extension responsibilities in corn production. Elmore can be contacted by email at or (515) 294-6655.

This article was published originally on 10/4/2010 The information contained within the article may or may not be up to date depending on when you are accessing the information.

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