CHICAGO, Aug 13 (Reuters) - The condition of the U.S. soybean crop improved last week, helped by recent rains that may boost harvest prospects for a crop that struggled through much of the summer due to the worst drought in five decades.
The rain also stabilized the corn crop, breaking a string of nine straight weeks where condition ratings dropped due to the scorching temperatures and dry soils, a U.S. Agriculture Department report released on Monday showed.
Ratings for both crops, however, remained at their lowest levels since 1988 and forecasts for harvest remained low even with the recent rainfall. USDA slashed its production and yield estimates for both crops in its supply/demand report released on Friday.
The government rated the U.S. soybean crop 30 percent good to excellent as of Aug. 12, up 1 percentage point from a week earlier and in line with the average of estimates in a Reuters survey of 12 analysts.
The improvement marked the first weekly uptick in soybean conditions since the government started rating this year's crop in early June.
"On the soybeans ... we perked up just a little bit," said Karl Setzer, grains analyst of MaxYield Cooperative. "The big thing is that we did not get any worse. The cooler temperatures, rainfall ... it has been a huge benefit. We could not have seen these rains come at a more perfect time in the development stage of the soybean crop."
The corn crop was rated 23 percent good to excellent, unchanged form a week earlier. Corn conditions also matched analysts' expectations.
The rain could raise harvest forecasts for soybeans, which are still in their critical yield-determining phase of development.
"The rains will help the soybeans that are filling," said Terry Basol, field agronomist with Iowa State University Extension. "The bulk of the soybeans that we have are in that seed fill stage. It is a long growth stage for soybeans."
Soybean plants reach their most critical stage of development -- called pod-setting -- about a month later than corn's reproductive pollination phase. They also can withstand drought a little better because they have a much smaller biomass than corn, and can idle their metabolic activity at night.
This year, both corn and soy plants are maturing one or two weeks earlier than usual after farmers took advantage of one of the mildest winters on record to plant seeds early and at a record pace.
Most of the corn crop has already passed through pollination and farmers were gearing up for harvest in many areas, so market watchers were not raising their harvest forecasts despite the turn to favorable weather.
"Some producers are harvesting corn already while others are finishing up final preparations to begin harvest," the Illinois field office of USDA's National Agricultural Statistics Service said in a report.
Light showers and cooler temperatures are forecast around the Midwest for the next week, said John Dee, an agricultural meteorologist for Global Weather Monitoring.
