Horticulture/Pre-emergent Herbicides
Pre-emergent herbicides are substances applied to the soil that prevent the successful germination of weed seeds. Timing is important when using these, as the applicator needs to know when to apply them: if applied too early, they may lose their effectiveness by the time weeds are germinating, if applied too late the weeds will already have grown beyond the point where they are vulnerable to this treatment.
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