Manual of the Trees of North America (Exclusive of Mexico) 2nd ed.

by Charles Sprague Sargent

XXVII. SIMAROUBACEÆ.

Trees or shrubs, with bitter juice. Leaves alternate, pinnate, persistent, without stipules. Flowers regular, diœcious; calyx 5-lobed, the lobes imbricated in the bud; petals 5, imbricated in the bud, hypogynous; stamens 10, inserted under the disk; pistil of 5 united carpels; ovary 5-celled; ovule solitary in each cell, anatropous; raphe ventral; micropyle superior. Fruit a drupe.

Of the thirty genera of this family, confined chiefly to the tropics and to the warmer parts of the northern hemisphere, three have arborescent representatives in the flora of North America. Ailanthus altissima Swing., the so-called Tree of Heaven, a native of northern China, has been largely planted as an ornament and shade tree in the eastern United States, and is now sparingly naturalized southward.

CONSPECTUS OF THE ARBORESCENT GENERA OF THE UNITED STATES.

Fruit a drupe or berry. Ovary deeply 5-lobed; fruit drupaceous.1. [Simarouba.] (D). Ovary not lobed; fruit baccate.2. [Picramnia.] (D). Fruit a 3-winged samara.3. [Alvaradoa.] (D).