Dog urine damage is often mistaken for disease problems.
Salts in dog urine can kill grass. The damage is easily confused with disease. Look for dead spots with greener grass around the edges. Female dogs and dry, infertile soil make problems worse.
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To reduce damage, flush with water immediately after dogs urinate or train them to go elsewhere. Rake up feces to prevent them from smothering and killing grass, providing an opening for weeds to get a foothold.