Crabgrass Killer is effective at killing several of the most common species of weeds without serious injury to the turf.
From an environmental point of view, Crabgrass Killer is one of the safest herbicides on the market. It's made from all-natural ingredients, none of which are harmful to your lawn, your pets, or your kids. The active ingredient is cinnamon bark, and the inert ingredients include baking soda, wheat flour, cumin, and corn flour.
It is one of the few selective organic weed killers. It's a powder and used by wetting and then dusting the weeds you wish to kill. During the hotter summer months, the grass in the very immediate area may turn slightly yellow temporarily, but no long-term damage will be done.
This can't be said for all herbicides.
In addition to the mentioned weeds, it seems to be effective on Virginia buttonweed, false strawberry and other fuzzy-textured weeds.