Presented below is a photomicrograph of a thin section of ginkgo leaf. This digital image was captured with the DXM 1200 ACT-1 control software in single-image acquisition mode utilizing apodized phase contrast illumination.

Ginkgo (Ginkgo biloba) is a common ornamental plant that is considered to be a living fossil. Also called the maidenhair tree, it is a deciduous gymnosperm (related to pine trees and cycads) that is the only living representative of the order Ginkgoales, once a widespread, dominant group of plants. Most members of this order are known only by their fossils, which date back to the Permian period, 286 to 245 million years ago. Fossil leaves similar to the living Ginkgo have been dated back to the Jurassic period, 208 to 144 million years ago. These fossils have been described from such geographically separated areas as Australia, western North America, Mongolia, Alaska, England, and central Europe.

A native of China, ginkgos were planted in ancient Chinese and Japanese temple gardens, to which the ginkgo may owe its existence today. Many botanists believe that it might have gone extinct had it not been preserved in cultivation. Some stands have been found growing wild in a remote mountain region of eastern China. However, it has not been determined if these are the last of the truly wild ginkgos or cultivated plants that found their way back into their native habitat.

The ginkgo is now grown around the world -- especially in China, Japan, and Korea -- valued as an attractive, fungus- and insect-resistant ornamental tree. It tolerates cold weather and, unlike most gymnosperms, can survive the adverse atmospheric conditions of urban areas and even atomic detonations. In Hiroshima, a ginkgo situated near a temple about one kilometer (0.6 mile) away from the blast center was the first tree to bud after the blast without any major deformations (the temple itself was destroyed). The tree continues to survive and a new temple was built around it.

One of the most distinctive features of G. biloba is its fan-shaped, bilobed leaves that resemble the leaflets of the maidenhair fern. Most leaves are divided into two lobes by a central notch. Dull gray-green to yellow-green in summer, they turn golden yellow in autumn, remaining on the tree until late in the season, and then falling rapidly. Multilobed leaves also occur on new branches (sucker shoots) arising from the tree trunk at ground level.