US wheat futures fell on Friday, pressured by the ongoing harvest of what is expected to be a big crop that will add to the global surplus of the grain. Chicago Board of Trade soft red winter wheat futures hit a nine-year low and K.C. hard red winter wheat hit a 10-year low during the trading session. For the week, the most actively traded CBOT soft red winter wheat contract fell 7.7 percent, its biggest weekly decline in two years.