US Commodities, the Iowa-based broker, has already warned that "crop quality will be a big concern this winter"."It is now a concern on how many bushels of #3 corn will hit the market," the broker added, referring to lower grade corn fit only for animal, rather than human, use.
Many crops are coming in light on so-called "test weights" – the actual weight of the crop per bushel of volume, and which can vary to between 45-60 pounds per bushel. Low test-weights signal a weaker protein composition in the grain, and higher concentration of starch, and are typical of crops that have not matured entirely. Higher moisture levels in damper crops are also a concern, limiting how much crop can be pushed through limited drier capacity.
US farmers managed to harvest only a further 5% of their corn crops in the week to Sunday, leaving 75% in the field. Typically, just 29% of corn is still left to be harvested by now. In North Dakota, where the harvest is usually half complete, just 2% of corn was in the silo – the same as the week before – meaning any progress was too limited to show up in the results.
In some states, the slow progress in corn has represented in part an emphasis on soybeans, viewed as a more vulnerable crop, during breaks in the cloud.
EDIT
http://www.agrimoney.com/news/us-corn-and-soybean-condition-falls-to-season-low--930.html