Maturing wheat. Photo: Blair Fannin, Texas AgriLife Extension In the past week, I have had several calls about wheat fields that showed severe ‘disease’ on the flag leaf. The symptoms were always described as a dying back of the flag leaf from the tip of the leaf downwards (Photo 1 and 2). This is not a disease but these symptoms are either caused by hot, dry and windy weather (Photo 1), a physiological phenomenon called leaf tip necrosis (Photo 2), or the combination of both.