The leaf spot is a disease caused by a fungus infection in the spring during periods of cloudy skies, high humidity and temperatures ranging from 15 to 25 º C. In combination with an overdose of nitrogen fertilizer. To reduce this infection: do not mow short, reduce nitrogen, dethatch and aerate the compacted soil. The infected leaves have oval spots ranging from purple to reddish brown. If the infection continues with favourable conditions all the foliage may die. To repair dead patches, over seed the lawn in the spring or by the end of August.