Dithiopyr
A pre-emergent herbicide with a unique advantage: it also provides some early post-emergent control of crabgrass in its first leaf stage. This wider application window makes it popular in areas where spring pre-emergent timing is uncertain.
Dithiopyr (sold as Dimension) is unique among pre-emergents because it remains active in the soil longer and can kill very young crabgrass that has just emerged (1-2 leaf stage). This makes it more forgiving if you miss the ideal timing window.
Duration: 3-4 months of soil activity, similar to prodiamine.
Best for: Lawns in climates where spring timing is unpredictable. Transition zone lawns where warm temperatures arrive unevenly.
Grass safety: Safe for most established turfgrasses. Check label for specific grass type clearances.
More on Pre-Emergent
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