The Ironwood Trees of the Untermainkai

A relative of the witch hazel has grown past 20 metres on the bank of the Main. The Persian ironwoods of the Untermainkai stand between 19 and 23 metres tall, by the city's register of natural monuments, and their crowns spread 19 to 22 metres across. They are entry 026 on that register. The species comes from the Hyrcanian forest, the band of old woodland south of the Caspian Sea. It takes its name from its wood, which is unusually hard. Frankfurt's own description adds the two things gardeners plant it for, gnarled stems with handsome bark and intense autumn colour. These are not single trunks. The register describes them as multi-stemmed and protects them in groups, with a 15-metre radius around each group, so on the promenade expect clusters of stems rather than clean single columns. What nobody has written down is their age. The city gives no planting year and no girth, and we will not guess at either. If you know when they went into the ground, tell us. The Untermainkai is a free public promenade along the river, open at all times. By our estimate it is about 8 to 10 minutes on foot from Willy-Brandt-Platz or Taunusanlage stations. The pin marks the group as a whole and is approximate, so the easiest time to find them is autumn, when the colour does the pointing for you.