Genus Ailanthus, Desf.
Leaves - compound (odd-feathered, but with the odd leaflet often dwarfed or broken off; leaflets, twenty-one to forty-one); alternate; edge of the leaflets entire, with one or two coarse, blunt teeth at each side of their base. Outline - of leaflet, long egg-shape or lance-shape. Apex - taper-pointed. Base, squared, or heart-shaped. Leaf/Stem - smooth, round, swollen at base. Leaflet/Stems - smooth and short. Leaf - one and a half to six feet long. Leaflets variable, usually about six inches by two and a quarter, rather smooth and thin. Bark - of the trunk, smooth and brown; the new shoots marked with whitish dots. Flowers - in long bunches at the ends of the branches; greenish, and of very disagreeable odor. June, July. Seeds - flat, at the centre of greenish and sometimes pink-tinged wings, in large, loose clusters. October. Found - common in cultivation, and to some extent naturalized. General Information - A large, showy tree (sixty to seventy feet high) of remarkable vigorous and rapid growth. It is a native of China. A Jesuit missionary sent its seeds in 1751 to England. In 1784 it was brought from Europe to the United States, and started near Philadelphia. Also about 1804 it was brought to Rhode Island from South America. But the source of most of the trees now found abundantly in the region of New York is Flushing, Long Island, where it was introduced in 1820. It has been a great favorite, and would deserve to be so still were it not for the peculiar and disagreeable odor of its flowers. Ailanthus, from a Greek word meaning "tree of heaven." Ailanthus - This spelling of the name should rule because so given by its author, although, etymologically, Ailantus would be correct, the native Amboyna name being "Aylanto."
Newhall, Charles S. The Trees of North-Eastern America (New York: The Knickerbocker Press, 1900) 187