I've always used granular herbicides until this year. Of course, I've sprayed glyphosphate but that's about it. For now, I'm just using backpack sprayers with either 3-Way, Sedgehammer, or Drive75. With the Drive, I'm using 1/3 oz. per gallon. The results I'm seeing are almost always the week after I spray crabgrass, it turns red throughout about 1/2 the plant. But quite often, it still looks healthy, just red and green. Sometimes it dies later, but it sure does seem to take a while. I think mixing and applying with backpack sprayers is actually harder to figure out than with large amounts such as with tank sprayers. Is the slow performance typical with Drive? Am I not spraying enough on the crabgrass? Do I not have enough surfactant? Anyone had similar results?