I've been using tribute a lot over summer for crowsfoot. Both spot spraying and blanket spraying on 328. I have had mixed results. At first I wasn't very impressed, the 328 seemed to brown off and the crowsfoot didn't die but I tinkered with the rates and applications a little and have been getting good results lately.I also tried half rate tribute half rate monument to target mullimbimby as well but that wasn't very successful. Think i need to up the rate a little. I have heard you need temps over 25C for tribute to be effective which just means the crowsfoots growing actively.