Technical Abstract: Management of wild oat and foxtail in spring wheat continues to be a challenge for producers in the Northern Great Plains. In making herbicide application decisions, there are many variables that are at best only partially known. The WheatScout decision aid was developed to integrate current scientific understanding of weed biology and economics to evaluate herbicide application alternatives for managing wild oat and foxtail in spring wheat. WheatScout builds upon the existing WeedCast model which uses daily weather information to estimate weed emergence and growth. WheatScout combines the weed emergence information of WeedCast with information on spring wheat growth, herbicide application windows and dose-response relationships, and effects of weed competition on spring wheat yields. The model uses observed and forecasted weather with field scouting observations to provide real-time information on herbicide options. Information is presented in a graphical display of current and future treatment options allowing the user to identify what options are available now, how long the options will be available, and what options are likely to become available in the future. In addition WheatScout provides estimates of the impacts of herbicide applications on crop yields, net returns and weed seed production, allowing comparisons among the available options. A test version of WheatScout is currently available. Field validation is currently being conducted at sites in Crookston, Rosemount, and Morris, Minnesota.