A: I have seen dozens of grass specimens over the last 2 weeks – all of these had root decays and leaf spots on them caused by fungi. Many of these diseases have been caused by a combination of the fungi and too much water. The fungi are naturally occurring in the soil and healthy grass does not fall prey to the disease except under perfect conditions.
Although there is little we can do about the rain, but we should not contribute to the problem by leaving our irrigation systems on. Please consider turning the irrigation system onto manual. I know it is hard to believe too much water can cause these kinds of problems but truly there is no other reason for root decay except too much water and/or poorly drained soil. Then, if we combine too much water with too much nitrogen, the two can certainly become deadly for the grass.
Just a few other things: water grass in the early morning (4am – 10am); mow grass on highest height, and keep mower blades sharp. Normally, we would tell you not bag your grass clippings, but if a disease is present on the grass blades, it is best to bag them and throw them away.