Date: July 10, 2001
Category: Diseases Subject: Gray Leaf Spot
GRAY LEAF SPOT ALERT IN MARYLAND
Dr. Peter Dernoeden from the University of Maryland has reported active
gray leaf spot in perennial ryegrass on their research farm, but no reports
from golf courses yet. He notes that this is the earliest record in his
area. Please watch for any unusual disease activities in perennial ryegrass
from now through the end of the season. Samples must be diagnosed with
a microscope. Other common ryegrass leaf spot diseases look similar. Fungicides
are very effective if used preventively or at the very early stages of
disease. Keep in mind that resistance to the QoI/strobilurin group (Compass,
Heritage) has been documented in turf for gray leaf spot.
