Rhamnaceae

Shrubs or small trees. Some branches ending in short thorns in Rhamnus. The European species (Frangula alnus and Rhamnus cathartica) found in New Brunswick are both highly invasive.

Leaves alternate or opposite, simple, stalked, with very prominent veins arising from both sides of the central vein; leaf edges sometimes wavy, with or without teeth; stipules present.

Flowers green or greenish white, solitary or in umbels in leaf axils, appearing at the same time as the leaves, or after the leaves. Each flower producing both pollen and seeds in Frangula; in Rhamnus and Endotropis each flower producing either pollen (male) or seeds (female) in separate flowers on the same plant or on separate plants, the flowers of one sex sometimes with non-functional remnants of the opposite sex. Flowers radially symmetrical. Sepals 4 or 5, fused at base to form a short tube. Petals in introduced species 4 or 5, small, separate; none in native species. Stamens 4 or 5. Carpels 2-5, fused to form 1 pistil; ovary surrounded at base by a large glandular disk; ovary located above point of attachment of other flower parts (superior). A stonefruit with 1-4 stones; each stone containing 1 seed.