A welcome relief to recent and prolonged dry period came this past week and now many are actively working on recovering from summer stress. Soil moisture should have been replenished and now with cooler weather and lower solar radiation, the turf systems should have some moisture reserve that might allow for a more aggressive approach to recovery. At the same time the moisture is helping with turf recovery, it is also helping with weed invasion, highlighting obvious chinch bug or grub damage, and of course late season dollar spot on golf course turf and high maintenance lawn areas with high populations of creeping bent grass and annual bluegrass.
Late season dollar spot is among the most difficult dollar spot problems to address as it seems to arrive very quickly (some say overnight). Also, as compared to much of the dollar spot symptoms and signs we observe during the season, this “strain” of dollar spot coalesce aggressively and result in very severe “pitting” of the turf when outbreaks occur. Our modeling research from 2003-6 revealed that the conditions conducive to these later season dollar spot outbreaks have increased in the last decade. Oddly enough what we learned from exploring the prediction is that dollar spot typically requires a dry period PRIOR to heavy dew for significant outbreaks to occur. Additionally there is some evidence that this population of dollar spot is more resistant to Thiophanate-Methyl. So keep on your usual dollar spot programs and consider some extra N to aid in any recovery form an outbreak that might have been missed.
Learn more here: Cornell Turfgrass Short Cutt.
