Pollen-mediated gene flow among crop cultivars and from crops to compatible relatives is an important issue for crops with regulated markets and with traits that may impact non-target organisms. The objectives of this project are to evaluate landscape-level crop-to-crop and crop-to-weed gene flow in wheat. Gene flow was estimated using pollen movement from ‘Above,’ a non-transgenic, imazamox-resistant winter wheat cultivar, to susceptible wheat and jointed goatgrass. Wheat and jointed goatgrass samples were collected in eastern Colorado in 2003, 2004 and 2005. Wheat samples from commercial fields were screened for resistance by treating with 44 g ha^-1 imazamox in field plots. Jointed goatgrass and wheat samples from Nelder wheel plots were screened in the greenhouse. In both the field and greenhouse, hybrids were identified by an injured (tillering) phenotype. Two wheat varieties (Jagger and Prairie Red) were found to have significantly (α=0.05) higher cross-pollination rates in 2003 than the nine other varieties sampled. No significant differences were observed in outcrossing rates among varieties in 2004. Cross-pollination rates of 0.01 percent to 0.5 percent were observed at the farthest sample distance of 37 meters in 2003 and 0.01 percent at 61 meters in 2004. The average cross-pollination rate for jointed goatgrass growing directly in Above winter wheat varied from 0.0 to 1.6 percent. Observed gene flow rates in wheat and jointed goatgrass are consistent with published reports.  Statistical evaluation of the wheat gene flow data will permit determination of appropriate isolation zones for different wheat cropping situations.