Features
Branching Out
Editor’s note: This is part of a series of columns highlighting some of the many interesting tree species that can be found on the U of G campus. It is written by certified arborist Rob Shaw-Lukavsky, a gardener in the Grounds Department.
Near the southeast corner of the J.D. MacLachlan Building stands a living fossil. The ginkgo tree (Ginkgo biloba) has existed on Earth for an astounding 150 million years and is known from ancient fossils dating back to the Jurassic period. The ginkgo has no close living relatives and is a taxonomical oddity belonging to its very own division, class, order and family.
Ginkgo is also known as the maidenhair tree because of its unique deciduous leaf shape and its similarity to maidenhair ferns. Individual trees are dioecious, being either male or female, and can take more than 20 years to produce fruit. Female trees produce cones, making ginkgos more akin to conifer trees than the broadleaf trees one would expect.
Ginkgo fruit and extracts are thought to have many medicinal uses, ranging from improved blood flow to treatment of memory loss and Alzheimer’s disease.
Ginkgos can grow to be very large. In China, they can reach over 150 feet in height and can live for more than 2,000 years. They are also incredibly resilient trees, as evidenced by the four that survived the atomic blast in Hiroshima, Japan. These trees still survive today, even though they are within two kilometres of the blast site.
Ginkgo trees are extinct in wild populations but are well-represented worldwide in parks and gardens and increasingly as street trees. They have virtually no serious pest or disease problems due largely to the fact that they evolved so long ago and so far ahead of any modern-day pest.