Research Summary Abstract
Clethodim, a grass herbicide, was first registered in the US as Select Herbicide for ornamental horticulture crops in 1983 with a limited crop list. From 1997 through 2007, the IR-4 Project completed 122 trials on 76 ornamental plant genera or species examining phytotoxicity related to foliar and/or drench applications of clethodim. In these trials, 7 species or genera exhibited minimal or no injury after foliar applications. Based on this information, it is suggested that all of these crops be added to the list of tolerant plants.