Imprelis (aminocyclopyrachlor) was released by DuPont Professional Products into the turf market in spring 2011 as a broadleaf herbicide. It is part of a new chemical subclass called pyrimidine carboxylic acids. Work conducted at Iowa State the past couple of years show Imprelis to be very effective against a broad spectrum of broadleaf weeds. Its advantage is that it is effective against several hard to control weeds such as ground ivy, violets, and henbit. It also has the advantages of being applied at very low rates of active ingredient and is rainfast, meaning that it does not need to remain on the weed leaves for a period of time. It is safe on most cool-season grasses and some warm-season grasses, including zoysiagrass. Anecdotal evidence suggests Imprelis may also have postemergence activity against crabgrass.
Iowa State University
Jones, Marcus and Christians, Nick E., "Residual Crabgrass Control and Broadleaf Weed Efficacy with Imprelis Herbicide" (2012). Iowa State Research Farm Progress Reports. 59.