The condition of US soybeans declined to its lowest of the season as rains last week proved insufficient to erase all concerns over dryness, including in the major producing state of Indiana.
The proportion of US soybeans rated "good" or "excellent" eased 1 point in the week to Sunday to 70%, the US Department of Agriculture said.
While still a strong rating, it was the worst of 2014 so far, and confirmed the crop as no longer the best of the last 20 years, falling behind the ratings curve for 2004.
The figure also defied market expectations of at least a stable condition rating, with some observers foreseeing some improvement after rains last week in many areas.
"The trade's expectations for improving crop ratings after last week's rain coverage was seen nearing 65% of the Corn Belt were unfulfilled," said Kim Rugel at Benson Quinn Commodities.
The decline reflected in part a further drop in the rating of soybeans in Kentucky, a relatively minor soybean producing state, but which has seen a dramatic drop in the health of its crop.
The proportion of Kentucky soybeans rated "good" or "excellent" stood at 58%, down 3 points week on week, and down 21 points since the end of June, reflecting largely a dearth of rainfall.
While the state did receive "much-needed rain relief" towards the end of last week, it followed a "very dry" spell which "saw moderate drought expand to consume 19% of the state", USDA scouts said.
However, the biggest decline in soybean condition week on week was in Indiana - a major Corn Belt producer, one of the "I" states with Illinois and Iowa - where the proportion of crop seen as good or excellent dropped by 4 points to 67%.
"Dry weather continued this week with only spotty showers," USD A scouts said, adding that "with the dry weather this week, irrigation was running where available".
The proportion of Indiana corn rated good or excellent fell too, by 3 points to 72%, although this was behind a 5-point drop in Kentucky, and a fall of 4 points, to 73%, in the reading for Michigan.
In Michigan, a mid-ranking corn producing state, "most areas need more precipitation, as some crops are showing stress, and pastures and hay fields are beginning to decline," scouts said.
However, while the condition of corn eased too in Iowa, the top producing state, it rose in second-ranked Illinois by 1 point to 82% good or excellent after "much of the state got a break from dry weather conditions last week".
In the major producing state of Minnesota, corn condition improved too, even though "most farmers would like to see their row crops receive additional moisture", scouts said.
The overall US corn rating stayed stable at a 73% good or excellent, the second highest reading of the last 20 years for mid-August, behind only 2004, which produced a record US yield.
The condition of US cotton eased for a second successive week, by 1 point to 52% rated good or excellent, with particular declines in Alabama, by 9 points to 60%, and Georgia, by 5 points to 62% rated in the top two grades.
In both states, a lack of rain has tested crops, with one Georgia scout noting that "dryland cotton is suffering and need rain in some areas".
In Texas, the top US cotton producing state, the proportion of the crop seen as good or excellent fell by 1 point to 37%, after a week of mixed precipition.
"Portions of the Lower Valley and south east Texas received 2 inches or more of rainfall. The rest of the state received little-to-no measurable rainfall last week," USDA scouts said.
A crop tour by Societe Generale highlighted a somewhat patchy crop around the state's key South High Plains cotton region.