Stephen Middleton from the Friends of Alexandra Park introduces us to his selection for May’s Tree of the Month…
With dramatic circular disc-like flowers, but without any petals or sepals, the May Tree of the Month is the Wheel Tree (Trochodendron aralioides). Stamens (male parts of the flower) radiate like the spokes of a wheel and the leaves of this tree are concentrated at the ends of the branches in a whorl. The Wheel Tree is a rare and strange tree and the only one in the park. You can find it flowering sometime between April and June.
Our tree is located in the Grove area of the park. Walk down the path from the Grove Cafe and it can be found just to the right of the path after the pine trees and adjacent to a willow-leaved pear – another example of last month’s tree of the month.
Wheel trees come from the far east and are native to Taiwan and central and southern Japan. In Japan it can sometimes grow as an epiphyte (a plant that grows on other plants). Specifically, this tree can grow on Japanese red cedars.
Another unusual feature of this tree is that in common with primitive plants it doesn’t have the long tubular vessels providing efficient water transport. In fact it is believed to be descended from plants that did evolve them before later giving them up for reasons yet to be explained. This is a little like the evolution of primitive sea creatures that first came onto land and then returned to the sea to become our present day whales.
The Wheel Tree was first brought to Europe (St Petersburg) in the 1860s before being grown in this country. It first flowered here at the end of the 19th century.
Although our particular tree is more like a large shrub, the tallest one in the UK has grown to almost 20 metres in height.
The scientific name Trochodendron literally means wheel (trocho) tree (dendron). The second part of the name describes the tree as looking like another tree called an aralia…… “aralioides”.
In Japan the tree has been used for building construction and as a glue.
While you are in this area check out the last of rhododendrons flowering.
