Millions of urban dwellers know the ginkgo primarily as a street tree, with elegant, fan-shaped leaves, foul-smelling fruits, and nuts prized for their reputed medicinal properties. But botanist Peter Crane sees the ginkgo as much more — an oddity in nature because it is a single species with no known living relatives; a living fossil that has been essentially unchanged for more than million years; and an inspiring example of how humans can help a species survive.
His new book, Ginkgo , tells the story of a tree that over centuries has made its way from China across Asia and around the world and today is found along streets everywhere from Seoul to New York. Peter Crane. How did you come to develop an interest in them? Peter Crane: I think that anyone who is seriously interested in plants inevitably comes across ginkgo pretty early in their training, because there are only five living groups of seed plants, and ginkgo is one of them.
And ginkgo is the only one that consists of just one species. Crane: Yes. When we think about flowering plants, there are about , living species. But the ginkgo is solitary and unique, not very obviously related to any living plant.
One of the points I wanted to draw out in the book is that in the past there were a variety of ginkgo-like plants, but this is the only one surviving. How do we know that? Crane: If you look at fossils from more than million years ago, you can see leaves that are very very similar to modern ginkgo leaves. But you have to look more closely to really assess whether those leaves were produced by plants that are identical to modern ginkgo.
And that work has been done now, by my colleague [Chinese paleobotanist] Zhou Zhiyan, who has worked on fossil material from China. If we could go back in a time machine, maybe we would find some differences, but I suspect not. Crane: A little over million years old. So it is a good example of a living fossil, like the coelacanth, which has also changed very little over millions of years. Ginkgo leaves in the autumn. What is with the smell? More than likely, it reflects some sort of adaptation or modification in its dispersal biology.
Probably either now or in the past the smell has been attractive to animals. But it must be part of a dispersal system. The interesting question is, are the things that adapted to disperse it still around?
Or are they extinct? It has been grown all over China since ancient times and is still often seen around temples there because it was once considered a sacred plant. It is especially common in western China. From China it was spread around the rest of the world as a popular ornamental tree when trade between east and west became routine. Such evidence of it has been found in America approximately as far north as the border with Canada.
The Ginkgo tree has been remarkably unchanged over its many years. It is undoubtedly their resemblance to the maiden hair fern that gives the alternate common name maidenhair tree.
Ginkgo is dioecious, which means male and female flowers are found on separate trees. The seeds are on the female trees and the pollen is on the male trees. The seeds are in the form of bare nuts. The nuts have no shells or covering, but a fleshy covering which has a very disagreeable odor.
Its name comes from the Japanese word "ginkyo. Pin Oak. The Ginkgo tree is the oldest living tree in the world and the only surviving member of the Ginkgo family. It supposedly has been around since the time of the dinosaurs, and one tree in China is about 3, years old. The tree species is native to Southeast Asia, but was brought over to the US in The seed of the Ginkgo is used for food, especially soup, the wood is used for religious furniture, and the leaves and nuts are used for medicine.
The Chinese and Japanese use Ginkgo in their Buddhist practices and have planted it around shrines and temples. Asian cultures also use Ginkgo frequently in their gardens and often plant it after an important life event.
Over the years Ginkgo has been used for many things in the medical area. It has been used as an herb to help with memory improvement and increase the blood flow rate in capillaries and arteries.
It has even been proven to fix some forms of erectile dysfunction. It is used to treat or help with so many different problems it would take a couple of pages to explain all them. The leaves of the tree can be toxic if large doses are eaten. They can cause skin disorders, mucous membrane irritations, and can cause intracranial hemorrhages. The Ginkgo likes to thrive in soil pH around 3. It has a dichotomous venation and tends to be seen in cities lining the streets. Scientific Name: Ginkgo biloba.
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