By Karl Plume
CORALVILLE, Illinois (Reuters) - The corn crop in central and western Illinois showed lower yield potential than last year as the worst U.S. drought in decades eroded grain production in the country's second largest corn growing state, scouts on a crop tour reported on Wednesday.
Corn in the typically high production areas of the state was under clear stress from temperatures that reached the triple-digits Fahrenheit at midweek, with leaves on many plants dried and brittle.
Plants in many fields were stunted with small, poorly pollinated ears.
Several fields observed by scouts on the five-day MDA EarthSat July Crop Tour in central Illinois were totally dead and likely to be plowed under by farmers.
Conditions improved modestly as the tour traveled into northwest Illinois, but crop yield estimates even there suggested a mediocre harvest at best, unlikely to offset the catastrophic crop losses in eastern Illinois and neighboring Indiana.
"Although plant health has improved as we move northwest, we still are seeing plants with signs of heat and drought stress," said Frank DiVito, a futures and options specialist with RCM Asset Management who was on the tour.
"This is leading us to believe that the lower yield expectations estimated thus far might not be entirely relieved by a more bountiful western Illinois and Iowa crop. As we move throughout eastern Iowa tomorrow we will get a better representation of this trend."
ILLINOIS YIELDS FALL
The first two days of the tour covered eastern Illinois, Ohio and Indiana, the worst-hit by drought this summer. Yield estimates for those areas were down about 30 to 60 percent from last year, the tour found.
The corn yield in nine fields surveyed in central and western Illinois on Wednesday were estimated at 159.9 bushels per acre, below an average of 167.1 bpa in the area last year.
The counties surveyed were Logan, Sangamon, Menard, Mason, Fulton, Peoria, Stark, Henry and Bureau.
One of the fields surveyed in Mason county was irrigated, but the yield estimate of 137.7 bpa was still below the county's average of 142.7 bpa last year, owing to poorly pollinated ears due to extremely hot weather during the critical pollination growth stage.
Many corn fields in one section of Menard and Mason counties between the towns of Petersburg and Kilbourne were completely dead as the area had received less than a quarter of its normal rainfall since the beginning of June.
Further north, crops were visibly stressed by heat and dryness with leaves curled and stalks turning brown from the ground up, known as 'firing.' But farmers may have helped some of the crop escape the hottest weather of the summer by planting 3 to 4 weeks earlier than normal.
But those crops were also beginning to show the typical signs of drought stress -- curled leaves and kernels not reaching the tip of the ears, known in industry parlance as "tip back."
The tour does not project soybean yields but instead records the crop's health and soil moisture to gauge yield potential.
Plants in northern sections of the area surveyed on Wednesday were relatively healthy, but those in the moisture depleted counties further south were withered by heat and moisture stress. Many of the plants still had flowers on them and could rebound if rains normalized.
The crop tour on Thursday and Friday will survey fields in top corn and soybean state Iowa, where the drought has intensified in recent weeks, before concluding in Omaha, Nebraska at week's end.
(Writing by K.T. Arasu; editing by Marguerita Choy and James Jukwey)
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