Thursday, December 3, 2009

THE CURIOUS GINKGO

Guest Contributor - Jim Woodworth, Director of Tree Planting


As an arborist with a passion and bias for native species, it took me a while to come around to fully embracing and appreciating the Ginkgo tree for all its fascinating virtues. It is quite a curious tree.

Consider that the gingko biloba is the most ancient of tree specie
s dating back over 200 million years to a region in China and it's also an urban survivor, tolerant of pollution, abuse and tight growing spaces. Its form and habit is so upright and oddly architectural, it strikes quite a pose, framing the narrowest of city streetscapes.

The ginkgo has my vote for the most vibrant and stunning yellow fall color, and the unique, fan shaped leaf (biloba, meaning "two lobes"--if you look closely you will see) even served as stationary letter head for the 1400 Monroe Street NW block association.

The fruit, produced by female trees, is the main reason the ginkgo tree gets a bad rap. Considered to produce an offensive smell by some, the fruit is highly valued by some Asian cultures for its taste and key to longevity. While the fruit can admittedly emit a strong odor, the smell is truly the culprit of individuals allowing the fruit to drop and remain uncollected. The simple solution is to collect and dispose of the fruit on a regular basis. Collecting the fruit when done routinely takes just a few minutes.

The obvious question is "why not just plant male trees if female trees produce the fruit?" Great question, tricky answer. The species has evolved the ability to change sex as needed to ensure an appropriate ratio of male and female. You may plant a male tree but presto chango, the tree may become a female down the road. Nothing you can do.

What about chemical control or reproduction you say? Unfortunately, spraying and injecting does not seem to reliably do the trick and can prove expensive and a time waster.

We continue to plant ginkgo trees for several reasons. They make great shade trees and diversity is the key to a healthy urban forest. No matter what tree you plant, all trees present some potential social negatives such as leaf or fruit litter or conflicts with hardscape. So instead of shaking your finger at the ginkgo, allow yourself to appreciate it.

Read more about the curious ginkgo tree and other DC Arbor Issues.

2 comments:

Anonymous said...

I love the Ginkgo tree! The shape is so irregular and the leaves cast a lacey shadow. Despite the bad rap for its smelly fruit, it is a great urban tree!

mhughes said...

The Ginkgo tree is one of my absolute favorites. I am completely in love. The fruit is no stinker than smelly cheese. Urban places often have much worse (and unnatural smells).

You too will fall in love with the ginkgo, if you see it in its full autumn spender.