The only common representative Genus of this Order in Canada is Fraxinus (Ash). The species of this Genus are trees with pinnate leaves, and polygamous or dioecious flowers without petals, and mostly also without a calyx; stamens only 2, with large oblong anthers. Fruit a 1-2-seeded samara. Flowers insignificant, from the axils of the previous year's leaves.
* Leaflets with petioles.
1. F. America'na, L. (White Ash.) Fruit winged from the apex only, the base cylindrical. Branchlets and petioles smooth and glabrous. Calyx very minute, persistent. Leaflets 7-9, stalked. - Rich woods.
2. F. pubes'eens, Lam., (Red Ash) has the branchlets and petioles softly pubescent, and the fruit acute at the base, 2-edged, and gradually expanding into the long wing above. - Same localities as No. 1.
3. F. vir'idis, Michx, f. (Green Ash.) Glabrous throughout. Fruit as in No. 2. Leaflets 5-9, bright green both sides. - Western Ontario and N.W., along streams.
4. F. quadrangulata, Michx. (Blue Ash.) Branch-lets often square, smooth. Leaflets sharply serrate, green both sides. Fruit narrowly oblong, of the same width at both ends, often notched at the apex, wing-margined. - Lake Erie coast.
* * Leaflets sessile.
5. F. sambudfo'lia, Lam. (Black or "Water Ash.) Branchlets and petioles smooth. Leaflets 7-9, sessile, serrate. Fruit winged all round. Calyx wanting, and the flowers consequently naked. - Swamps.