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Chicago futures helped as low prices spark demand

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Ample supply continues to weigh on market

(Updates for market close)

By Heather Schlitz

CHICAGO, Aug 8 (Reuters) - Chicago wheat, corn and

soybean futures chopped up and down but ended lower on Friday as

traders weighed a bounce in demand fuelled by low prices against

expectations of ample supply and upcoming U.S. government crop

forecasts.

All three crops had rebounded in the previous session after

wheat struck a five-year low, soybeans a four-month trough and

corn contract lows during Wednesday's session.

The most-active wheat contract on the Chicago Board of Trade

(CBOT) fell 3-3/4 cents to $5.14-1/2 a bushel. CBOT corn

fell 1-1/2 cents to close at $4.05-1/2 per bushel, and

CBOT soybeans settled 6-1/4 cents lower to $9.87-1/2 per

bushel.

Higher than anticipated weekly U.S. export sales reported by

the U.S. Department of Agriculture had supported Thursday's

bounce, suggesting low prices were generating demand.

A series of flash sales of corn in recent days to Mexico,

Guatemala and unknown destinations have also helped support

prices.

Short-covering also helped wheat and corn prices rebound as

traders exited their positions ahead of an upcoming USDA report.

Grain markets are now shifting their focus towards monthly

USDA supply and demand projections due on Tuesday, which will be

closely watched for revisions to expected U.S. corn and soybean

production.

The U.S. is expected to produce bumper corn harvests later

in the year. Analysts polled by Reuters think the U.S.

Department of Agriculture will raise its estimates in a monthly

report due on August 12.

Expectations of plentiful supply have weighed heavily on

prices as growing conditions for U.S. corn and soybeans appeared

ideal.

"Cosmetically the crops all look really really good," Mark

Schultz, analyst at Northstar Commodity, said.