The Hackberry of the Plaza de Murillo

The Plaza de Murillo, the small formal square between the Prado's south door and the gate of the Royal Botanic Garden, holds four catalogued conifers and one broadleaf that outgrew every one of them. This hackberry stands 25 metres tall, close to the recorded ceiling for the species, and is about 140 years old, which puts its planting in the decade the square took its present shape. Celtis australis is the almez, a southern European tree with a smooth grey trunk that looks poured rather than grown, and fruit the size of a pea that turns from orange to near black. Spanish villages once coppiced it for the handles of hayforks, because the young wood bends a long way before it snaps, and whole valleys in Aragon lived off that trade. It is also, unglamorously, one of the toughest street trees in existence, indifferent to drought, wind and exhaust, which is exactly why a specimen this size is still standing on an island of pavement in central Madrid. Look for its flowers in April and you will not find them; they are green and smaller than a grain of rice. Stand under it in July, when the stone outside the Prado is at forty degrees, and the reason the square was planted this way needs no explaining.