* Wheat falls after hitting highest since June 30
* Low export demand weighs on corn
* Soy mixed, with new-crop pressured by crop expectations (Recasts with updated U.S. prices and additional quote; changes byline and dateline)
By Mark Weinraub
CHICAGO, Aug 7 (Reuters) – U.S. wheat futures fell on Thursday, dropping back from a 5-1/2 week high on a round of profit-taking following a six-session rally that had pushed prices up 9.2 percent, traders said.
“We came pretty far, pretty fast off our lows,” said Chris Robinson, senior trader at Top Third Ag Marketing. “It is not surprising that we get a little bit of a breather.”
Read Also

U.S. tariffs looming large over canola market
U.S. tariffs are one market headwind facing Canadian canola prices, but Chinese levies are another wrinkle coming down the pipe for farmers.
Corn futures also fell, weighed down by light demand on the export market. Soybeans were mixed, with the front-month contract supported by tight supplies, while old-crop contracts sagged on expectations of a huge harvest.
Traders said the wheat market was in focus due to concerns about how the conflict between Russia and Ukraine would affect exports from the Black Sea region.
In a sweeping response to Western sanctions imposed over Russia’s support for rebels in Ukraine, Russian Prime Minister Dmitry Medvedev said on Thursday his country will ban fruit, vegetable, meat, fish, milk and dairy imports from the United States, the European Union, Australia, Canada and Norway. Moscow is the second-biggest importer of U.S. poultry.
Chicago Board of Trade soft red winter wheat for September delivery was down 4 cents at $5.64 a bushel at 12:05 p.m. CDT (1705 GMT)
Some short-covering, spurred by speculation that the Ukraine crisis could deepen in coming days, kept the declines in check and pulled wheat from its session low. Traders also cited some technical support for CBOT September wheat at its 40-day moving average.
CBOT September corn was 5-1/2 cents lower at $3.57-3/4 a bushel, with expectations for a bumper harvest keeping bargain buyers on the sidelines even with prices near four-year lows.
The U.S. Agriculture Department said on Thursday morning that new-crop export sales of corn were 758,700 tonnes in the latest week, below trade estimates ranging from 800,000 to 1 million tonnes.
“The world has moved into a period of surplus in the corn market, so the function of the market has become to weaken farmer margins and discourage production,” Macquarie analyst Christopher Gadd said.
An export trader said that most world buyers were more interested in Black Sea corn, which was priced about 15 cents a bushel lower than U.S. supplies.
CBOT soybeans for August delivery were 5-1/2 cents higher at $12.42-1/2 a bushel, while the new-crop November contract was 5-3/4 cents lower at $10.74-1/4 a bushel.
Prices at 12:06 p.m. CDT (1706 GMT) LAST NET PCT YTD CHG CHG CHG CBOT corn 357.75 -5.50 -1.5% -15.2% CBOT soy 1242.50 5.50 0.4% -5.3% CBOT meal 389.70 1.70 0.4% -11.0% CBOT soyoil 35.53 -0.26 -0.7% -8.5% CBOT wheat 563.50 -4.50 -0.8% -6.9% CBOT rice 1271.00 8.50 0.7% -18.1% EU wheat 176.25 -2.00 -1.1% -15.7% US crude 97.27 0.36 0.4% -1.2% Dow Jones 16,401 -43 -0.3% -1.1% Gold 1312.30 6.31 0.5% 8.9% Euro/dollar 1.3350 -0.0031 -0.2% -2.2% Dollar Index 81.5690 0.1250 0.2% 1.9% Baltic Freight 765 6 0.8% -66.4% In U.S. cents, benchmark contracts, except EU wheat (euros) and soymeal (dollars). CBOT wheat, corn and soybeans per bushel, rice per hundredweight, soymeal per ton and soyoil per lb. (Additional reporting by Naveen Thukral in Singapore and Nigel Hunt in London; Editing by Peter Galloway)