By Tom Polansek
CHICAGO, Aug 30 (Reuters) - Chicago Board of Trade grain and soybean futures fell on Monday after favorable weekend rains in the U.S. Farm Belt and on expectations that approaching autumn harvests will boost supplies.
Rains across Iowa and Minnesota benefited crops, brokers said, after dryness threatened fields in parts of the Midwest earlier this summer.
"The debate is on: How much did that rain help us?" said Don Roose, president of Iowa-based brokerage U.S. Commodities. "The vote today is it helped."