One of the oldest living fossils--or plant genera that lived during ancient times and still lives on earth today is the remarkable maidenhair tree (Ginkgo). Leaf imprints of an ancestral species of Ginkgo resembling the present-day Ginkgo biloba have been found abundantly in sedimentary rocks of the Jurassic and Triassic Periods (135-210 million years ago) when dinosaurs roamed the earth. All North American plantings of this splendid tree are living descendants of trees only known from the orient, cultivated by people in temple gardens for countless generations. Petrified (permineralized) logs of this tree have been uncovered from their ancient tomb of flood sediments and lava flows near the Columbia River Gorge of central Washington. They once formed great forests in this region 150,000 centuries ago.
http://waynesword.pa...0601.htm#fossil
