Late summer chlorosis has usually indicated a treatable mineral deficiency in my trees. My English oak often becomes chlorotic in
August/September and is rapidly greened up with a small dose of Epsom salts (teaspoon to the gallon). In other cases I have successfully used trace element "frit" at the next repot or watered with fertiliser containing the full spectrum of plant nutrients.

Kev Bailey
Vale Of Clwyd, North Wales

Roger wrote
"I have experienced some chlorosis on one or two of my trees, although usually not until later in the summer, from time to time. Other than continuing routine fertilization I have never tried to do anything about it, although I probably should. I would be interested to hear if you eventually can correct your situation."