Ancient trees

Ancient trees

Not many species can claim to have outlived the dinosaurs, but trees can. There are some trees shown in the fossil records, Magnolia, Sequoidendron, Ginkgo and some varieties of pine. There are living examples which can be aged to 2000-3000 years old. So next time you think about how old this tree will get, be careful of the variety you choose.

Magnolia is a large genus with up to 210 species. They can be evergreen or deciduous. They have flowers that range from white to dark pink and occasionally yellow. The flowers appear on bare stems as star and bowl shapes and attract beetles for their pollination. This is because the magnolia evolved long before the bees did. Magnolias will grow in heavy, clay soils; they are tolerant of atmospheric pollution, but they should be sheltered from cold winds and frosts.

The Sequoiadendron giganteum can live over 3000 years. It is a coniferous tree found in the Sierra Nevada mountains, and there are fewer than 80000 remaining trees. The largest of these trees measures to 85m tall with a trunk 8m diameter, which is big enough to drive a car through. There are approximately 11,000 cones on a large tree, which produce between 300 and 400 thousand seeds annually. In the UK, the tree is commonly known as Wellingonia, whereas everywhere else, it is known as Giant Red Wood. The largest known example in the UK can be found in the New Forest and stands at 52.73m tall. There are currently 500,000 trees in the UK, whereas in California, there are only 80,000 trees remaining. The Sequoiadendron is important for the storage of carbon; a 45m tall tree can store up to 15 tonnes of carbon. The most giant trees in California can store a callosal 250 tonnes of carbon.

Without a doubt, the grandest of our ancient trees is the Ginkgo biloba, commonly known as the Maiden Hair tree. The common name derives from the fan shape of the leaf, which radiates veins through it. The leaves, which can be 12cm wide, are green through summer, turning a magnificent golden yellow in autumn. Despite being a conifer, the Ginkgo is deciduous; it is also dioecious, meaning the trees are either male or female. It will grow in well-drained soil and generally achieves 12m in the first 20-50 years. Eventually, it will reach 25m tall, though there are some who can get to 50m and live over 2000 years old. Evidence of their existence can be found going back 290 million years ago, as shown in fossil records.

The most outstanding Ginkgo we know about are the ones which survived the Hiroshima atomic bomb dropped near them on 6th August 1945. There are six specimens which are within a mile of the bomb site, seeds from which have been distributed around the globe to encourage world peace. Some of these seeds are grown in the UK at Glasgow Botanic Gardens.

Posted 22nd Mar 3:11pm