Last year I showed cool-season (C₃) and warm-season (C₄) growth potential (GP) in relation to overseeding timing in Japan and in Dubai. Larry Stowell from PACE Turf suggested I look at another way of representing the growth potential. He said that if I would plot time on the x-axis, and the cumulative sum of the difference between C₃ GP and C₄ GP, I would see something very interesting related to the transition from good warm-season weather and good cool-season weather.

I've looked into this by analyzing the daily C₃ GP and C₄ GP using weather data from the past 15 years at Kashima, Japan. Read the report and see the charts here.