Maple leaf is a Canadian icon. It is the symbol of Canadian identity. The Canadian flag has a red maple leaf on a white background. The symbols of Canada can heighten not only our awareness of our country but also our sense of celebration in being Canadian. They are a celebration of what Canadians are as a people.
Thus, when Kate Middleton wore a red maple leaf hat on her visit to Canada, it showed her recognition of the Canadian symbol. On several other occasions, Kate Middleton wore a maple leaf brooch which she borrowed from Queen Elizabeth. The Queen (then Princess Elizabeth) wore this brooch in the shape of a maple leaf during her first visit to Canada in 1951.
This diamond encrusted maple leaf brooch was originally presented to Queen Elizabeth- the Queen Mother on her visit to Canada in 1939.