 That's one of the things. And, of course, there was a time period when the lawns were always dewy and wet in the spring. Well, and some people, they might be heading out of town, so they get out there early in the morning. Why? Do you damage it that way then? A moist lawn, even a dewy lawn, will tend to pick up those spores of that fungus and carry it further. So avoid mowing a lawn when it's dewy or wet.