Fig. 1. Average daily soil temperatures at 10-cm depth from Grand Forks, ND, during autumn in 1999 and 2003. In 1999, once soil temperature dropped below 10°C, it stayed low for the remainder of the cold season, which is the desired scenario for fall-applied nitrogen fertilizer. In contrast, in 2003, after first dropping below 10°C, soil temperature rose above this level three times, which possibly enhanced nitrogen losses.