Olszyk, D.M., C.A. Burdick, T.G. Pfleeger, E.H. Lee, and L.S. Watrud. 2004. Assessing the risks to non-target terrestrial plants from herbicides. J. Agric. Meteorol. 60(4):221-242. WED-04-157
Use of chemical herbicides to reduce weed competition is a major contributing factor to the high productivity of conventional intensive agricultural cropping systems. However, because of their inherent phytotoxicity, movement of herbicides from target crops and soils can adversely affect non-target terrestrial plants. We review current trends in herbicide usage, evidence for effects of herbicides on non-target plants, and risk assessment methodology used to determine potential non-target effects of herbicides. Persistent questions regarding whether or not standard plant tests and analysis protocols provide adequate information for risk assessments, lead us to suggest research needed to improve the risk assessment methodology for effects of potential herbicide drift on non-target plants. This research includes spatial analysis to identify non-target plant species at risk, and development of new biochemical/molecular, phytotoxicological, and ecologically based tests.