Trees: Ginkgo Biloba


Ginkgo biloba;  Pronounced GINK-oh by-LO-bah

The Gingko is the second oldest tree known to mankind, with fossils found dating back 270 million years ago well before the dinosaurs roamed the earth. What is remarkable about this tree is that it has remained virtually unchanged since that time.

Once it populated the entire globe, but as the dinosaurs died out and with it the tree’s primary means of seed dispersal together with climate chage its numbers withered until it was thought by European botanists to be extinct.

But tucked away in a handful of Chinese and Japanese Buddhist temples the Gingko, against all the odds, survived, tended and nurtured by the loving hands of temple gardeners and Buddhist priests who considered it a tree of mystical powers.

German botanist Engelbert Kaempfer first discovered the Gingko in 1691 growing in the grounds of Japanese temple. Adopting the local name Gingko – Chinese for “silver apricots” because of the fine down that coats the seeds before they are ripe – he brought the seed back to Europe to propagate and from that day its majestic height and spectacular autumnal colour  has made it a favourite in public parks and open spaces across the continent. 

Fossils remains indicate many different sorts of Gingko once existed, but only one species has survived today.  Linneaus, the 18th century Swedish botanist whose classification of plants is still used, discovered the Gingko to be unique. Though primitive, it was neither fern nor conifer, so he devoted an entire division of the plant kingdom to this one species of tree.  Hopeful that more varieties would one day be discovered he gave it the distinguishing adjective “biloba” because of its bi-lobed leaves. It’s these leaves that have given the tree its popular name “The Maindenhair Tree” because of it’s similarity to the Maidenhair fern.

Gingko biloba has a remarkable ability to survive.  When the tree is in distress little aerial outgrowths called chichi appear on the upper trunk. These are disease resistant and grow downwards into the soil to form roots and clones of the old tree appear.  But astonishingly, when the atom bomb was dropped on Hiroshima in August 1945 six boles remained standing within 1.5 Km from the epicentre of the blast where temperatures reached up to an estimated 500,000 degrees C. The following Spring the trees, one by one, began to leaf.  One cannot imagine the emotional effect this must have had on the population of this devastated city. Not surprisingly the tree become known as “the bearer of hope”. In the States it was planted as the UN Peace Tree in the ‘50s and Yoko One planted one in Detroit in the millennium year for people to tell their wishes to.



The Chinese recognised early on the medicinal importance of the tree which is why it was nurtured in monasteries and temples. Every part of the tree – leaf, bark, root and seed are used in Chinese herbal medicine in the treatment of everything from asthma to Alzeimers and even cancer.  Its seeds are offered as side dishes at Chinese banquets for guests to nibble between courses to aid digestion. Western scientists began to investigate these properties in the 1950s and managed to synthesize extracts from the tree to use medicinally. This won Dr. Elias Corey the Nobel Prize for Chemistry in 1990.

It’s not however a tree for the back garden. Growing anything up to 50 metres high it’s only been appropriate up to now in public spaces. Also the trees are dioecious, requiring both male and female plants to survive and a drawback is that the seeds produced by the females are unpleasant to the smell, so female trees are rarely found in public parks. But today there are many nurseries devoted to the creation of smaller varieties of the tree suited to the garden.


 
Location of Ginkgo trees in the park is indicted by the dark green leaf symbol with the yellow dot. A female tree has the letter 'f' to distinguish it.