GRAINS-Soybeans, grains weighed down by big harvest prospects
* Wheat tumbles after higher crop estimates in Canada, Ukraine
* Midwest crop tour findings for corn look mixed
* Soybeans fall for second straight session (Adds analyst's comment, tour findings, closing U.S. prices)
By Rod Nickel
WINNIPEG, Aug 24 (Reuters) - U.S. soybeans and grains dipped on Wednesday, weighed down by abundant harvest prospects in key countries.
Soybeans led the way lower, as the closely watched four-day Pro Farmer U.S. Midwest Crop Tour scouted impressive crops in central Illinois, following its observation a day earlier of above-average soybean pod counts in Nebraska and Indiana.
Southwestern Iowa's soybean crop potential, however, looked below average.
U.S. soybeans benefit from strong demand, due to production shortfalls in South America, "but we're still going to have a big crop," said Bill Gary, president of Commodity Information Systems in Oklahoma City. Continuación...