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Photographer: GardenSoft
Physical weed control, including mulching, or hand removal protects the watershed from harmful chemicals.
Consider replacing some lawn areas with groundcovers, trees, and shrubs. Good candidates for removal are portions of large lawns, areas where no one uses the grass, patches that don't grow well, or spaces too small to water without overspray.
Remove irrigation water and fertilizer from areas where you don't want weeds to grow.