1933 94 820 Tufts and Morrow found fruit-bud differentiation of the Napoleon cherry beginning in early July.
1937 Apr. 16/2 The Napoleon cherry had also been badly injured by the major peach borer.
1998 (Nexis) 10 Sept. f10/1 Seckel pears and Bartletts won't pollinate each other, and your Napoleon cherry will barely talk to a Bing.