Ginkgo: The Tree that Remembers Time

Ginkgo’s striking beauty is resident in every leaf – the tree’s common name reflects the similarity of the elegant fan-shaped leaves to the maidenhair fern. The meaning of the leaves and their pattern of diverging raised veins are both beautiful and memorable. The leaves are meditated on and celebrated by artists from Goethe’s poetry to Hossein & Angela Valamanesh’s beautiful Ginkgo Gates at the western entry to Adelaide’s Botanic Gardens. Confucius is even supposed to have taught beneath a ginkgo, and ginkgos are commonly associated with temples in China, Korea, Taiwan and Japan. The butter yellow autumn foliage and the synchronous fall of the leaves are celebrated and in Sewanee in the USA are sown to make devotional Advent yellow roses – a rather beautiful craft and an apt symbol for everlasting life. Ginkgo is the most exquisite example of a living fossil. Ginkgo dates back to Jurassic (and of course the contemporaneous dinosaurs) and yet survives to represent one of the five lineages of seed plants extant today. Curiously while ginkgo has been in cultivation for at least 1000 years and is represented by a rich fossil record there are only two wild populations of ginkgo persisting and even the origins of these populations are disputed by botanists. At the end of the recent Shanghai Chenshan Botanic Gardens Symposium I joined a few local and international botanists on a pilgrimage to Tianmu Mountain in Zhejiang Province, a few hours north of Shanghai to see the ancient remnant forests that one of these wild populations. The populations consists of a couple of hundred trees and a fabled specimen supposed to represent five generations that perches on the edge of a cliff at an altitude of 950 metres. The Chinese have described this tree as, “an old dragon trying to fly” and seeing half of the tree cascading over the precipice in the mist the allusion seems apt. The tree has 15 stems with the largest over a metre in diameter. As if the ginkgo isn’t reward enough the rest of the Mountain’s flora is breathtaking in it’s diversity and beauty (and deserves further attention in these pages). The botany of ginkgo is as remarkable as the tree. Commonly planted trees are male as the small apricot-like fruits of the female have a flesh that smells like vomit. However the fruits contain a nut that’s widely regarded in Asia and female trees might be prized if you don’t have to walk over the fruits each morning. The fertilisation process is quite primitive and involves the development of motile sperm – perhaps a riskier strategy than that of flowering plants but one that’s been effective for 200 million years. Sir Peter Crane, former director of the Royal Botanic Gardens, Kew and currently Dean of the School of Forestry & Environmental Studies at Yale was in Shanghai for the Symposium. Peter has recently completed an evolutionary and cultural biography of ginkgo initially founded on his research into ginkgo’s fossil record (Ginkgo: the tree that time forgot published in March by Yale University Press). Peter’s narrative incorporates his paleobotanical research, the ethnography of ginkgo’s cultivation and distribution and our relationship with this extraordinary tree. Peter’s conclusions are as much metaphysical as scientific – ginkgo’s endurance for 200 million years reminds us of the transitory history of humans. A number of ginkgo’s that survived within a mile of the centre of the atomic bomb blast in Hiroshima remain and perhaps reinforce the qualities for endurance that ginkgo might have and that humans might not. In Sir Peter’s words, “… (humans) evolved to live in the present, so we’re very focused on the short-term. One of our biggest shortcomings is that we can’t see the long-term, and we see that in the way we respond to all kinds of environmental issues.” Ginkgo’s idea of the long-term makes an economist’s long-run a heartbeat. Stephen Forbes is the Executive Director of the Botanic Gardens of Adelaide