Answer: There are post emergence herbicides for crabgrass control (Bayer Advanced All in One Weed and Crabgrass Control, Spectracide Lawn Weed Killer) but if you have already used Spectracide, maybe the weed is not crabgrass but something else. I would dig some more out and get a second opinion. Not all herbicides are safe to use on all turfgrass types so a positive identification of the weed and of your turfgrass are really important. You can take a sample of both to your local cooperative extension office for help (3800 Cornucopia Way # A, Modesto). You'll find lots of information on control measures at the extension office, as well. Best wishes with your lawn.
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