TechNotes Tips - 06.21.01

Hot humid weather throughout the transition zone of the United States has the potential to wreck havoc on cool season turfgrasses. Brown patch (Rhizoctonia solani) is a potential problem on both tall fescue and perennial ryegrass. This disease is normally associated with nighttime temperatures above 70 F. In situations where moisture or high humidity is present like in shaded situations, brown patch can occur at nighttime temperatures below 70 F. For more information on brown patch see:
http://www.ianr.unl.edu/pubs/plantdisease/g688.htm
http://hgic.clemson.edu/factsheets/HGIC2150.htm

Red thread continues to be a problem on perennial ryegrass turfs in the northern United States.

Hot dry conditions the last several days in the Midwest has resulted in wilting of Kentucky bluegrass and perennial ryegrass turfs. Wilt symptoms are easily noticed by the bluish tint of the turfgrass. If rain is not received this week, lawns showing severe wilt should be watered.