Excessively hot temperatures in much of the Midwest, and Iowa in particular, during the first 2 weeks of August is limiting the 2010 corn yield.

While heat indices reached into the 100-degree-plus range in early August and stayed warm throughout the nighttime hours, corn ears were not able to rest overnight. And that, what essentially translates to a lack of sleep for corn plants, has ear tip back and kernels not filling out to the end of the ear.

The official Pro Farmer yield estimate for corn is 164.1 bushels per acre nationally, and a range of 162.5 bushels per acre to 165.7 bushels per acre. That should amount to a total crop of 13.29 billion bushels with a range of 13.157 to 13.423 billion bushels. The total crop estimates are figured using USDA’s harvestable acreage number in the August 12 Crop Production Report of 81.005 million acres.

By comparison, USDA’s August 1 yield estimates were 165.0 bushels per acre, with a total crop prediction of 13.365 billion bushels.

"This was the most mature crop we’ve probably ever tested on the Pro Farmer Midwest Crop Tour," says Chip Flory, Pro Farmer editor and west tour director of the annual trip to sample actual field data from seven Midwestern states. "But there is not denying this a large crop. If we could have just gotten another quarter-inch on the grain length, that would have made a world of difference."

The Pro Farmer estimates have a margin of error of +/- 1%, but Flory believes there is little upside potential to this corn crop, because it's so far advanced.

While this crop looks to bring in the largest ever total production, there are questions about meeting the demand in the coming year, Flory says. USDA has projected usage for 2010-11 at 13.49 billion bushels, leaving this year’s production some 200 million bushels short.

With an already tight carryover anticipated for corn this year, ending stocks heading into next year’s harvest are expected to approach the 1-billion-bushel mark. That’s the point where the trade begins to really worry about supply and demand balances.

"I don’t believe we’ll get below 1-billion-bushel carryover, but we will probably see some price rationing, and maybe we already are seeing it, if USDA’s projected yield drops any further," Flory says.

Soybeans are expected to increase nearly a full bushel over last year’s final yield of 44 bushels per acre. The 2010 Pro Farmer production estimates for soybeans is a yield of 44.9 bushels per acre, with a range of 44 on the low end to a high-end yield of 45.8 bushels per acre. If realized, this will produce a crop of 3.5 billion bushels, with a range of 3.43 billion bushels to 3.57 billion. There is a margin of error in these numbers of +/- 2%.

USDA’s August 1 projection for soybean yield was 44 bushels per acre for a total crop of 3.43 billion bushels.

"I don’t believe you can argue that we have a very good bean crop," Flory says. "As far as the pod counts we looked at on the tour, we were looking at a mid-September type of crop, not a mid-August type.

"Last year, for example, we saw a lot of fields with a late flush of blooms on the tour and they produced some beans. This year, that late flush has already happened, so we were looking at the pods that will be there for harvest."

As both regions of the tour moved closer to Iowa, sudden death syndrome (SDS) became more evident in fields. The biggest questions for the soybean crop remain in Iowa, where the SDS situation is the most prevalent, he says.

"Iowa is the swing state," Flory says. "If disease pops up and really damages the crop, we’ll be looking at the lower end of the yield. If it doesn’t, we could see the yield move higher.

"There was just no denying there were a lot of pods out there and we’re looking at a big bean crop."