Like Paul Gray, I grew up playing a course that would brown out in the summer, and after the first rainfalls, would begin to green up again.
Though the leaf is brown, the root structure is still alive.
Must say that I have heard of courses adding fairway irrigation after the hot summer in Europe some years back, claiming they lost the turf. I wonder whether it is true or not, whether it was an excuse to put in fairway irrigation so the place would remain green.