Gingko

Humans think in decades, forests operate in centuries, but the land’s timeframe spans hundreds of millions of years.  We can read prehistoric stories not only in fossils and bedrock, but also in the few ancient species of plants that survive to this day.  Ginkgo (Ginkgo biloba) is one of these.

Photo 1: Ginkgo (Ginkgo biloba) on PEI. I've been watching this slow-growing tree for more than three decades and there's been little noticeable change in its size.

Ginkgo’s direct ancestors can be traced back to the Permian – a time before dinosaurs when the sediments that would become PEI’s red bedrock were still being eroded from the Appalachian Mountains. Fossils take tens of millions of years to form and the species that made them are almost always long extinct by the time they are ever discovered.  Our Island is rich in fossils of trees such as Calamites, Lepidodendon, Pecopteris, and Walchia, all of which disappeared before or during the Permian-Triassic extinction event about 250 million years ago. (You can see local examples of these fossils and read more about them here: https://www.pei-untamed.com/post/permian-to-present-2-fossils).  

Ginkgo survived and, in the hundreds of millions of years that followed, thrived across what is now Asia, Europe, and North America.  It witnessed the evolution of birds, mammals, flowering plants and pollinating insects; saw the rise and fall of dinosaurs; and survived two more major extinction events. The fossil record shows that Ginkgo began to decline several million years ago, and it was presumed to have been extinct until ‘rediscovered’ in China in the late 1600s (though its presence there was known by the local people long before this). Today, Ginkgo is considered native to China but has been widely planted as an ornamental tree around the world, including here on PEI.

As an ancient plant, Ginkgo doesn’t fit into modern boxes. Neither a broadleaved tree nor a conifer, it’s the only remaining link between plants that reproduce by spores (such as ferns) and those the reproduce by seeds (such as conifers).  Ginkgo’s fan-shaped leaves are unlike those of any other tree but do look a bit like the unrelated Maidenhair Fern (Adiantum pedatum), giving rise to its other common name, Maidenhair Tree.

While there have been several Ginkgo species over the eras, the one that exists today has been unchanged for about 60 million years.  You don’t survive that long without being highly resilient.  Ginkgo is hardy to a range of habitats, tolerant of pollution, and resistant to pests and fire. As dramatic evidence of this last point, Ginkgo trees in Hiroshima survived fires caused by the atomic bombing of 1945. Individual Gingkos are slow-growing and can live thousands of years.

Ginkgo’s ecology and history are fascinating, but this tree is best-known for medicinal uses that date back centuries.  It has been traditionally used to relieve respiratory and intestinal issues, and more recently to increase blood flow, improve memory, and reduce the symptoms of age-related dementia and Alzheimer's disease. Although Ginkgo is one of the top-selling herbal supplements in North America, it can interact with some prescription and over-the-counter medications and it’s best to check with your health care provider before using it.

I’ve been watching one particular Ginkgo in Charlottetown for decades now and can attest to how slowly this species grows.  I do like to visit and imagine it among the prehistoric forests and wildlife, millions of years before the appearance of humans. It is one of the most interesting parts of PEI untamed!