Jim, Image herbicide is effective in controlling two of the South's most difficult weeds, nutsedge and dollar weed. Follow package instructions noting best application times for nutsedge which is an important part of the treatment. Do not expect to see 'overnight' results. It may be a month before you are satisfied that it is working. It probably will take you a few years of treatment to get on top of a serious nutsedge problem as its seeds appear to be viable for decades.

Jim, it's taken me 4 years of twice a season applications of Image to get where the nutsedge is only in two smaller portions of our lousy supersod lawn. The trick is to space the applications about 3-4 weeks apart during the most active growing season which is July. I used a handheld sprayer and the small packets for this process, diluting it in water per instructions. Image also comes premixed but you can never tell how old the solution is or how it's been stored so I prefer the foiled packets so I know it's fresher and potent.
I'd wait until mid July to start the treatment.