This is from another site...
A Canadian Maple leaf on a white circular background was carried on both sides of the fuselage under the windscreen. Its colour has been a matter of some controversy. In his memories, Johnson stated that the the leaf on his aircraft was green. However, all the Canadian squadrons of the Kenley wing had this national symbol painted in red. Was green the conscious decision on the part of Johnnie to underline his British origin, or did the memory fail him on this rather small detail? Perhaps we will never know.