About Sequoia Trees
Sequoiadendrons can be traced to the Triassic Period 200 million years ago when dinosaurs first appeared. Sequoiadendrons were the dominant tree in North America and Europe during the Jurassic Period (180 to 135 million years ago) and the Cretaceous Period (35 to 70 million years ago). Dinosaurs disappeared near the end of the Cretaceous Period but the Sequoiadendrons lived on. The planet was significantly warmer and wetter during dinosaur times and the atmosphere was much richer in carbon dioxide. The earth was more fertile for plant and animal life in those days. The proof is found in the carbon deposits of coal beds and oil fields that formed during those times. Much of the carbon that was once in the atmosphere is now locked up in coal and oil deposits and is now unavailable for plant use. The ancestors of the giant sequoias were fed and watered by a rich and thriving earth.
At the end of the Cretaceous Period the earth began to cool and dry. The Sequoiadendrons began to slowly retreat in favor of plant species more suitable to the dryer conditions. About 20 million years ago Sequoiadendrons became extinct in Europe but still survived in Western North America. The Sequoiadendron giganteum, the only surviving member of the Sequoiadendron genus, was relegated to the western slope of the Sierra Nevada Mountains in what is now known as California about 2 million years ago. In the Sierra Nevada only a few areas are suitable for the continued existence of the big trees. These areas have relatively deep soil and permanent moisture in the soil. The Giant Sequoia groves are fed moisture from streams, springs, and subsurface moisture coming down from higher ground.
It has been said that the giant sequoias are living dinosaurs. In truth they are far more than that. They originated earlier in time and outlived the dinosaurs by 70 million years. Today, thanks to its best friend, man, giant sequoias can be found growing in many places over the earth.