A firm start to 2011-12 for corn exports has left US farm officials too gloomy in their forecasts, signalling that stocks may end up tighter than they are currently predicting, Allendale said.

"In addition we fell the strong export pace justifies a 50m-bushel increase over the USDA's latest estimate," Rich Nelson, Allendale's director of research, said.

Such a revision would lift US corn exports to 1.65bn bushels (41.9m tonnes), if still leaving them down 10.1% year on year at their lowest since 2002-03, the broker said.

Allendale pegged the important year-end stocks figure, a signal of the tightness of corn supplies and thereby of their price potential, at 795m bushels, 71m bushels below the current USDA figure.

Strong, but for how long? 

The broker's comments follow a strong start, on paper, to 2011-12 for US corn export sales, which reached 806m bushels as of October 20, seven weeks into the season, 25m bushels ahead of the figure a year ago, boosted by China's purchase of 78m bushels (2.0m tonnes).

"Small [US] sales in the week ended October 20 and recent announcements that several importers are buying corn from other sources has created some concern about the strength of export demand for US corn," Professor Good said.

'Back to the top of the agenda'

Allendale's comments came ahead of an estimate from analysts at Informa Economics of a 149.5 bushel-per-acre US corn harvest, unchanged on the consultancy's October figure.

And they followed the release by rival broker FCStone of estimates showing the corn yield at 148.4 bushels per acre, 0.3 bushels per acre below its forecast last month.

"Although we don't see large changes to yield and production estimates for the US corn and soybean crops, tightness in the corn market in particular is being nudged back up to the top end of the market's agenda," Jaime Nolan Miralles, at FCStone's Dublin office, said.

'Demand for US soybeans will recover'

FCStone also lowered its forecast for the US soybean yield, by 0.6 bushels per acre to 42.2 bushels per acre, with Allendale trimming its estimate by 0.1 bushels per acre to 41.4 bushels per acre.

US export sales so far this season have been significantly slower than a year before, with buyers such as China switching some of their demand to South America.

Nonetheless, Oil World on Tuesday raised doubts that South American sellers had many soybeans left to sell thanks to the strong trade, which it estimated rising by 3.2m tonnes, or 64%, year on year in September and October.

"World demand for US soybeans will recover in November and continue to rise in December and January, when most of the South American soybean stocks will have been disposed of and South American exports are seasonally small," the influential analysis group said.