Corn data looks likely to provide the highlight of a bumper day for agriculture statistics on January 12, with analysts unusually divided over the blow dealt by a delayed harvest to US production hopes.

On average, analysts believe the US Department of Agriculture will cut its estimate of American corn production by 100m bushels to 12.82bn bushels because of the slow pace of harvesting, with 30% of North Dakota's crop still in the field as of last week.

However, the mean conceals a huge variation in assessments of the impact of the delays, which reflect persistent rain in both sowing and harvesting periods.

"If there is going to be a surprise, it will  be a large drop in production due to the crops unharvested and left in the fields until spring," said Tim Hannagan at broker PFG Best, which foresees a 211m-bushel decline.

"The [USDA] has never had to address this degree of a problem."

Rabobank also flagged the "large variation" in estimates and the difficulty of assessing the harvest in a note forecasting a USDA revision to near the consensus figure.

Soybean record

Forecasts for the USDA's figure for US soybean production in its January world supply and demand crop report are more closely bunched around the 3.34bn-bushel consensus, setting a record by an extra 19m bushels than foreseen in the December document.

The estimate for end-2009-10 corn stocks is expected to be trimmed too, thanks to a revival in demand for ethanol, for which the grain is a major feedstock.

Wheat plantings

The USDA will also unveil its first estimate of US winter wheat plantings, which analysts on average believe have fallen by 2.81m acres to 40.50m acres.

However, there is some spread of estimates too, with Prudential Bache Commodities forecasting a fall of only 815,000 acres, while Farm Futures estimated a 4.92m-acre decline.