IUCN Red List Category: Extinct in the Wild. This means that there is no doubt that all natural populations of these species have died and that a species is only known to survive in cultivation or in populations that have escaped from cultivation well outside of the natural range of the species. This native tree was collected from the banks of the Altamaha River in southeastern Georgia by John Bartam and his son William in 1765 and has been extinct in the wild since 1803. It is thought to have been brought to extinction largely through over-collection by nurserymen.
IUCN Red List Category: Critically Endangered. This means that that the tree is facing an extremely high risk of extinction in the wild in the near future. Fossils found of this tree date back nearly 100 million years, to the late Cretaceous period of the Mesozoic era, when dinosaurs still walked the earth. This tree closely resembles the American species bald cypress, but can be distinguished by the opposite buds. The areas surrounding the forests where this tree is found heavily cultivated and the forests where the tree is found are in imminent danger of being converted to farmland. Currently, the tree does not reproduce well, and is highly sensitive to disturbances such as those from agriculture, making prospects for natural regeneration poor.
Red pine (Pinus resinosa) is native to northeastern North America and higher elevations of the Appalachian Mountains. It is relatively common in Canada but is endangered in Illinois, with just one tiny population left in this state. It is becoming rarer as climate change warms our region and the conditions in which this tree can grow shift to the cooler north.
There is some good news, though. This species represents a conservation success story!
Restoration and reforestation efforts throughout the Great Lakes region have helped increase numbers of red pine. Several dwarf and ornamental varieties of red pine have been developed by breeders, and these managed trees have become a popular Christmas tree.
What can you do? Support legislation that reduces CO2 emissions and make an effort to minimize your carbon footprint, to mitigate climate change. Some ways to do this include eating less meat, turning off lights, reducing food waste, and walking or cycling instead of driving.
Jack pine (Pinus banksiana) is a small, sometimes shrubby tree native to Canada and northern parts of the U.S. Illinois is at the far southern end of its range, so while it is relatively common in the northeastern U.S. and Canada, it is now very rare in Illinois.
Jack pine cones need fire to open and disperse the seeds. Because forest fires have been suppressed across much of its southern range, it has a hard time reproducing here. Jack pines will continue to disappear from Illinois and other U.S. states as our climate warms and the populations move farther north to more suitable habitat and colder conditions.
In Michigan, an endangered bird called Kirkland's warbler lives only in jack pine forests. If jack pines continue to decline, so will this endangered bird.
What can you do? Plant jack pine in your yard to support local wildlife
Koyama's spruce (Picea koyamae) is a tall cone-bearing tree native to just a few isolated locations in Japan. It is extremely rare in the wild, with only a few hundred trees remaining.
This species is critically endangered because it is being out-competed by other tree species that are being planted nearby for timber. When Koyama's spruce trees are lost due to logging, fire, or typhoons, trees of other species move in to replace this endangered spruce.
Scientists have analyzed the genes of this species and determined that its small, fragmented populations are not reproducing with one another. This genetic bottleneck makes the species even more susceptible to extinction.
What can you do? Be a champion of trees and advocate for tree conservation. Support botanic gardens and arboreta that conduct threatened tree research and conservation.
Dawn redwood (Metasequoia glyptostroboides) is a Chinese relative of the giant redwoods and sequoias that grow in California. Dawn redwood is slightly smaller than its huge American cousins, but can still grow up to 200 feet tall. Dawn redwood is unusual in that it is a deciduous conifer, losing its needles in winter and regrowing them again in spring. An older tree will form distinctive wide buttresses at its base and has a trunk that tapers toward the tip.
This species was originally known only from fossils. We thought it had been extinct for millions of years, but then some dawn redwoods were discovered growing in a small area of central China. The species is endangered in the wild in China because of over-harvesting and habitat destruction, which is made worse because the trees reproduce very slowly.
Luckily, several botanical gardens around the world are growing large conservation groves of this species to ensure dawn redwood will not go extinct.
What can you do? Support botanical gardens and arboreta that grow dawn redwood in their collections. You can think of an arboretum as a lifeboat for endangered trees!
Note: This dawn redwood marks the entrance to our exhibit Vanishing Acts: Trees Under Threat, which also highlights endangered trees from around the world. We encourage you to continue your tour of threatened trees by taking the wood-chipped trail through the Vanishing Acts exhibit. The loop will return you to this spot to continue this self-guided threatened tree tour.
Ginkgo (Ginkgo biloba) is a long-lived tree. The oldest known ginkgo is 3,500 years old! The species itself is often called a "living fossil," because it hasn't changed much at all since it first evolved around the same time as the dinosaurs, over 200 million years ago. It is probably the oldest tree species in existence. It is also the only species in its genus, family, order, and class, so it represents a pool of unique genetic diversity: It is not closely related to any other plant lineage alive today.
Ginkgo is a commonly cultivated tree, thriving in city parkways and gardens around the world because of its tolerance for urban conditions such as air pollution, salt spray, and poor or compacted soil. This is surprising, since it is actually endangered in its native range in China! The ginkgo is slow-growing and slow to reproduce, and its habitat is being destroyed by human activity. Ginkgo is also subject to over-harvesting because it is widely used in traditional medicine to treat a variety of ailments including dementia, anxiety, schizophrenia, and blood clotting.
What can you do? Plant a ginkgo in your yard, and share its story with your friends and neighbors to raise awareness of threatened trees.
Katsura (Cercidiphyllum japonicum) is a medium to large tree native to Japan and China. It has thick, flaking bark and beautiful heart-shaped leaves that turn bright colors in the autumn, making it a popular ornamental tree around the world. However, in the wild this tree is threatened by habitat destruction.
What can you do to help the katsura survive? Support botanical gardens and arboreta that conduct horticultural and conservation research on threatened trees. Share your knowledge of threatened trees with friends and family to build awareness for the importance of tree conservation
Paperbark maple (Acer griseum) was first discovered by Western botanists on a plant collecting expedition in China in 1901. Can you guess why it's called "paperbark maple"? It is treasured as an ornamental tree for its coppery, flaking, paperlike bark and three-lobed leaves.
Despite its horticultural popularity, it is very hard to grow from seed. Tree breeders would like to have more genetic diversity to work with as they develop new ornamental varieties of this species.
Paperbark maple is endangered in the wild in China because its populations are isolated and trees often produce seeds that do not sprout. Scientists from The Morton Arboretum are conducting field work in China to investigate the levels of genetic diversity left in the wild and identify populations of paperbark maple that harbor the most genetic diversity. These populations of trees are the most important to protect for conservation and horticultural purposes.
What can you do? Support The Morton Arboretum and its science and conservation programs. The Arboretum’s Center for Tree Science collaborates with scientists around the world to help us better understand, grow, and save trees.
Recognize this tree? Fraser fir (Abies fraseri) is America's favorite Christmas tree! It has been chosen as the official White House Christmas tree more than any other species.
Native to the Appalachian Mountains, it is under threat from the balsam woolly adelgid, an invasive insect pest that was introduced into the U.S. from Europe in the early 1900s. Infestations of this pest kill mature trees, reduce viability of seeds, and make the trees more susceptible to fungal infections. Currently, we have no practical way to prevent adelgid infestations in the wild.
Scientists with the U.S. Forest Service and collaborating universities are studying the genetic diversity of the small remaining wild populations of Fraser fir. They are collecting seed to protect in a seed bank to ensure this species does not go extinct.
What can you do? Avoid harvesting a wild Fraser fir as your Christmas tree (farmed Fraser firs are okay, because farms usually maintain their own seed orchards). If you do cut down your own Christmas tree from the wild, choose spruce or another species of fir instead. Prevent the spread of invasive insects by not moving firewood between campsites.