Academics cautioned over the threat to some US winter wheat seedlings from dryness, and pests, even as official data showed some stabilisation in the condition of the crop, thanks to some "much-needed "rains.
US Department of Agriculture scouts reduced their rating on the condition of winter wheat in Kansas, the top growing state, to 32% viewed as "good" or "excellent" as of Sunday.
However, that represented a decline of just 1 point week on week.
"Areas in the eastern half and northwest received some much-needed precipitation in the form of light rain and snow," USDA scouts said, while acknowledging that totals were limited to less than half an inch.
'Signs of recovery'
In Texas, the proportion of winter wheat rated good or excellent remained steady at 11%, even though winter grains crops in the Cross Timbers area "showed signs of recovery following recent precipitation".
"Warmer weather along with thunderstorms, high winds, and increased humidity were reported in many areas of the state."
And in Oklahoma, where south eastern farms received an average of 0.8 inches of rain in the weekend to Sunday, the proportion of winter wheat rated good or excellent held at 17%.
'We need moisture'
Nonetheless, UDSA scouts cautioned that "significant moisture is needed across the whole state, assuredly in the Panhandle and south west for winter wheat development".
And a crop tour by Oklahoma State University warned that time was running out for rains to arrive.
"The primary concern for all of Oklahoma remains lack of moisture," Jeff Edwards, small grains specialist, said.
"There are some fields in north central and north western Oklahoma with good yield potential; however, the best areas are starting to turn blue due to lack of moisture.
"Another couple of weeks of warm temperatures and wind without rain will turn blue wheat to brown. We need moisture."
The dryness has, besides directly depriving wheat seedlings of moisture, prevented the uptake of nitrogen fertilizers and encouraged the spread of pests, the Oklahoma State University tour found.
"We simply have not had enough moisture to get good movement of top dress nitrogen into the rooting profile and for the wheat crop to take up applied nitrogen," Dr Edwards.
His colleague Tim Royer, university entomologist, warned that the main pest concern was brown wheat mites, which "can severely damage wheat that is already stressed due to drought or other adverse environmental conditions.
"They feed by piercing plant cells in the leaf, which results in 'stippling'. As injury continues the plants become yellow, then dry out and die."