It's that time of year again when summer induced chlorosis begins to show up on lawns, golf courses, and sports fields. I have already had a few calls on this problem. Summer induced chlorosis is a yellowing of the turf that occurs as temperatures rise in midsummer. We normally see it in late July and into August. This year has been a little cooler than normal, but the few warm days that we have had are triggering the problem in some areas.
David DeVetter, a graduate student at ISU, completed a masters project on this in 2007. Here is the link to the article.