Why is it Important to Winterize Sprinkler Systems?
What to do if the affected spots and grass are stimulated?
If the affected spots are green and grass growth is stimulated (no browning is apparent):
1. Increase nitrogen fertilization frequency and/or the amount of fertilizer to help mask the urine-induced stimulation of growth and color; dark green spots will be especially visible on lawns that are not receiving adequate nitrogen fertilization.
2. Maintain adequate irrigation to prevent accumulation of salts in the soil; drought or lack of water can allow salts to accumulate and injure or kill turf.
Source: ColoradoStateUniversity Extension for this information (December 2010 – Fact Sheet #553).