Michigan Trees: A Handbook of the Native and Most Important Introduced Species
dd. Leaves finely and abundantly toothed; bark longitudinally
white-striped; a bushy tree or shrub.
aa. Leaves compound; twigs usually with whitish bloom. _A. negundo_, p. 193.
+WINTER KEY TO THE SPECIES OF ACER+
a. Terminal buds usually under 1/4 inch in length.
b. Buds white-woolly; twigs usually with a whitish bloom; opposite leaf-scars meeting; fruit often persistent on the tree until spring. _A. negundo_, p. 193.
bb. Buds not white-woolly; twigs without whitish bloom; opposite leaf-scars not meeting; fruit not persistent on the tree in winter.
c. Buds reddish or greenish; twigs bright red.