During USGA Course Consulting Service visits throughout the Northeast this spring, conversations focused on frequent rain as many areas endured 7 to 9 inches in just a few weeks. These conditions inhibited deep, robust root development, which was concerning. However, June is normally a mild weather month that is favorable for growth. Unfortunately, summer arrived early and we entered the “ring of fire” and “heat dome” that gave us a stretch of temperatures well into the 90s with high humidity, leading to turf stress that’s more typical for August than June.
Turf managers were already trying to keep up with mowing and managing the impacts of heavy play, then the weather made things even tougher! There are many resources on managing summer stress but what is actually happening? We see the thinning turf canopy, yellow leaves and short roots, but as the great turf pathologist Dr. Peter Dernoeden would say, summer decline may be more of a physiological response rather than a pathological problem.
Of course, pest problems are more significant when the turf is stressed, but why? Heat stress creates an imbalance with energy production and consumption in the turf. Respiration is high and the ability to photosynthesize is low, so stored carbohydrates are consumed leading to noticeable root depletion. When spring aeration is skipped or extended periods of poor weather lead to limited rooting, the turf’s ability to perform and defend against pathogens is weakened. Combine high temperature stress arriving early with weak roots and exercising caution now for better turf later becomes critical.
Summer stresses arrived quickly this year, so the play right now is to increase photosynthesis and carbohydrate production by maintaining more leaf surface through practices such as rolling instead of mowing on occasion and/or slightly raising heights of cut. Reducing soil temperatures, watering to what the turf needs, minimizing mechanical stress and increasing the frequency of plant health applications should be prioritized to protect the playing surfaces. We cannot predict the future, but we can be cautious. Sometimes doing nothing is better than doing something. Reach out to your regional USGA agronomist if you want to discuss plans for the months ahead – or if you just need a little reassurance!
Northeast Region Agronomists:
Darin Bevard, senior director, Championship Agronomy – dbevard@usga.org
Elliott L. Dowling, regional director, East Region – edowling@usga.org
Brian Gietka, agronomist – bgietka@usga.org
Information on the USGA’s Course Consulting Service
Contact the Green Section Staff