1. Leaves pinnately compound; corolla none; fruit a samara; tree.

Fraxinus

1. Leaves simple or rarely trifoliolate; corolla conspicuous; fruit a capsule or berry-like drupe; shrub.

2. Flowers yellow, solitary or in groups of a few along the stem appearing very early before the leaves expand.

Forsythia

2. Flowers white, pink, or purple, in terminal panicles appearing after the leaves are partially or fully developed.

3. Flowers in panicles less than 7 cm long, white; fruit a berry-like drupe.

Ligustrum

3. Flowers numerous in a dense panicle at least 7 cm long, often pink or purple; fruit a capsule.

Syringa