Height: up to 40m high
Winter buds: black, arranged in opposite pairs.
Leaves: compound, opposite and usually have 3-6 pairs of leaflets that are distinctively pointed. There is a single leaflet at the end of the leaf.
Flowers: male and female purple flowers.
Fruit: winged fruits hang in clusters (keys) and turn brown after leaf fall.
Distribution: found in woods, along hedgerows and in streets and parks. Rare in northern Scotland.