4. Fráxinus quadrangulàta, Michx. (Blue Ash.) Leaflets 7 to 9, short-stalked, oblong-ovate or lanceolate, pointed, sharply serrate, green on both sides. Fruit narrowly oblong, blunt, of the same width at both ends, or slightly narrowed at the base. A large tree, 60 to 80 ft. high, with smooth square twigs on the vigorous growths. Wisconsin to Ohio and Kentucky.
F. platycárpa.
5. Fráxinus platycárpa, Michx. (Water-ash.) Leaflets 5 to 7, 3 to 5 in. long, ovate or oblong, acute at both ends, short-stalked, slightly serrate. Branchlets terete, smooth to pubescent. Fruit broadly winged, ¾ in. wide, often 3-winged, tapering to the base. A medium-sized tree in deep river-swamps, Virginia and south.
F. sambucifòlia.
6. Fráxinus sambucifòlia, Lam. (Black Ash.) Leaflets 7 to 11, sessile, oblong-lanceolate, tapering to a point, serrate, obtuse or rounded at base, green and smooth on both sides; when young, with some rusty hairs along the midrib. Fruit without calyx at base and with wing all around the seed-bearing part, blunt at both ends. A slender tree, 40 to 70 ft. high, with dark-blue or black buds.
F. excélsior.
