Interest in forestry research evaluation has steadily increased in recent years. This paper describes an ex ante model, which uses forecasts of the future benefits of current and proposed research to evaluate a research program that focuses on enhancing pine growth by controlling competition from herbaceous weeds. A principal value of this model is its potential for wide applicability to other forest management research programs. The method requires information describing pine growth impacts, the probability of future research success, the probability and rates of future technology adoption, the management strategies of potential users of the technology (weighted by the area and site quality of lands under their control), the costs of research extension, and technology adoption, and the future value of stumpage. Past and planned herbaceous weed control research will produce substantial net economic benefits through the application of research findings to the management of pine forest types in the southern U.S. for. Sci. 36(2):313-329.