A tree to look out for this autumn is the Sweet Gum, a tree rarely seen 20 years ago but now widely planted both as a street tree and as an ornamental, largely due to its reliable truly splendid autumn colour, the leaves turning a rich variety of orange, red, browns and purple before they fall, often all varied on the same tree. Mostly quite small because recently planted, they can be seen as street trees in Herne Hill and Burbage Road, and there is a pleasing row on the left as you go into Dulwich Picture Gallery Garden from Gallery Road.
In Dulwich Park there are two very large specimens beside the Lake with huge leaves almost as large as those of Chestnuts, though not divided to the base as separate leaflets. One of these trees is actually labelled and gives opportunity to appreciate the deeply fissured bark – a characteristic not yet developed on the younger trees.
The leaves unfold in May and are rich shiny green looking like a pointy leaved maple but always alternately placed on the twig, not, as in maples, in opposite pairs. The male and female flowers are not very striking and can usually be found on the same tree and the little brown furry nut-like fruit are very decorative.
The Sweet Gum’s resin is known as STORAX and is used in soap making and perfumery; the timber, known as Satin Walnut, is used for fine cabinet making and inlay work
The tree comes from the South Eastern coast of The United States and was introduced by John Banister He was a missionary and botanist in Virginia, employed by Henry Compton, Bishop of London from 1675-1713 who made the gardens of Fulham Palace, famous for the exotic trees and plants he assembled there. John Banister also sent the first Magnolia (Magnolia virginiana) to be cultivated here, the Scarlet oak,(found in Court Lane Gardens and College Road), and the Honey Locust (Gleditsia triacanthos), being used as a striking street tree in Idmiston Road where its amazingly long flat pods litter the ground every autumn.
I do not know how successful his missionary work proved to be, but we owe much in our landscape to his work as a collector.