Monday, October 10, 2011

ABOUT GINKGO TREES…

Yesterday, my botanist friend, Vickie, led me to a site in front of Convocation Hall here on the Sewanee campus, where the Bentley Bells and chimes ring out from Breslin Tower, to show me a beautiful tree whose attractiveness was overpowered by a rancid butter odor. The Ginkgo biloba or Maidenhair Tree, that occupies this site had dropped a gracious plenty of seeds on the ground, and although I stepped carefully on the lawn around the perimeter of the tree, I brought home some seed on the soles of my sandals and had to do a major clean-up to get rid of the unpleasant sour smell.

At the time of the sighting, the tree hadn’t turned its golden autumn color, and its stature indicated that it had guarded the old hall for years. I imagine that most people walk on the sidewalk beside the Gingko, rather than crunching around on the ground beneath it as I did during my investigation, which caused the unpleasant vapors to rise into the air. The smell lingered for half a block.

The Gingko tree in Europe was first sighted by German botanist Engelbert Kaempfer in a Japanese temple garden during the 17th century. It’s a living fossil dating back 270 million years, and at the end of the Pliocene Era during the Ice Age, it disappeared, except in an area of Central China where Buddhist monks are said to have saved the tree from extinction. Today, some species in China tower to heights over 164 feet.

The Gingko tree possesses strong survival characteristics, withstanding heavy winds and snow damage, two weather conditions prevalent at Sewanee during the winter seasons. The tree has been cultivated in North America for over 200 years.

Gingko trees are designated as dioecious – in other words, the trees are either males or female. The females produce a seed that is yellow brown and fruitlike, not unattractive in appearance, but it’s the culprit that contains butanoic acid which emits an unpleasant smell like vomit.

In an interesting article about the Gingko, an Iowa City office manager complained about a Gingko tree growing in front of her business that caused a slimy mess and which she described as emitting a smell that was “pretty disgusting.” Throughout the U.S., some city councils and businesses have removed female Gingko trees, leaving the “non-stinky” male trees in their environments as they’re excellent shade providers. Incidentally, Frank Lloyd Wright acclaimed the Gingko as his favorite tree.

In defense of the smelly Gingko (the national tree of China), extracts of Ginkgo leaves contain flavonoid glycosides and terpenoids (ginkgolides, bilobalides) that are used to treat dementia. Gingko is believed to be effective in enhancing memory in humans and as an anti-vertigo agent. Also, Gingkolides are used in treating and preventing cardiovascular and central nervous system diseases.

Six Gingko trees, still alive and well, that survived the 1945 atom bomb explosion in Hiroshima, Japan attest to the durability of these wonderful trees. I don’t know how old the Sewanee Gingko tree is, but some botanists predict that Gingkos can live 3,000 years!

In Oriental cultures, the Gingko tree represents changelessness, as well as unity, hope and love.

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