10 Tree Facts for our 10th Anniversary!

10 Things about Trees You Probably Didn’t Know

By Lauren McVittie

In celebration of ten years of ReForest London in 2015, here are ten things you may not have known about our favourite leafy friends.

1. Christmas trees have seven times more genetic material than humans 

Swedish researchers mapped the gene sequence of the Norway spruce, a species commonly used as Christmas trees. Their study was published in the journal Nature in 2013.

Over several hundred million years of evolution, conifers have developed repetitive DNA sequences. This repetition accounts for the sheer volume of DNA. Other plant and animal species have evolved to eliminate repetitive DNA.

2. The largest genome ever sequenced belongs to the loblolly pine 

Coniferous trees have a lot of genetic material! The Norway spruce genome was the largest genome to be sequenced, until scientists at the University of California-Davis mapped the genome of the loblolly pine. Their research was published in Genome Biology in 2014.

Like the Norway spruce, much of the pine’s DNA was repetitive – 82 percent in fact. 

3. Trees are nature’s air conditioners 

Trees evaporate water into vapour through their leaves. The cooling effect of this evaporation from just one tree can be equal to ten room size air conditioners running twenty hours a day!

4. The art of growing bonsai trees is over 2000 years old 

Trees also have substantial cultural importance. Bonsai is the art of growing miniature versions of trees. Pruning, wiring, and other techniques shape otherwise normal plants into tiny trees. It literally means, “planted in a container” in Japanese.

The practice began in the Chinese empire and 1000 years later, it was adopted in Japan.

5. Trees make neighbourhoods more walkable 

Streets that have trees encourage people to walk more. This can influence your physical health, and also your mental health. By having more people walking, imagine how many more people you could meet in your community.

Trees also have a traffic-calming effect. Simply put, trees make our communities more liveable! 

6. Full trees appear on six national flags 

Lebanon has a cedar, Belize has a mahogany tree, Peru has a cinchona, Equatorial Guinea has a silk cotton tree, and both Figi and Haiti’s flags feature a palm tree. 

Many more territory flags feature trees, and many flags feature parts of trees – such as the maple leaf on Canada’s flag.

7. The Whomping Willow in the Harry Potter movies is based on a chestnut tree 

An old sweet chestnut tree in the Kew Royal Botanical Gardens in southwest London, England provided the bark texture for the Whomping Willow. A plaster cast was used to capture the pattern of its bark.


8. Not all conifers are evergreens 

Evergreens are trees that keep their needles in the winter. However, some trees are deciduous conifers. The Tamarack tree (also knows as Larch), for example, is a deciduous conifer whose needles turn yellow in autumn before the tree sheds them in the winter.

9. The Amazon Basin and Guiana Shield area has 16,000 different tree species 

This large region in South America is known for its incredible biodiversity. In 2013, scientists reported there are nearly 400 billion individual trees in this area.

10. Ontario’s largest tree is taller than a 13-story condo 

At 47 meters tall, this eastern white pine was crowned with the title of Ontario’s tallest tree in May 2015. The tree is located in the Gillies Grove Nature Reserve along the Ottawa River. The Nature Conservancy of Canada (NCC) and Forests Ontario made the announcement in time for the International Day of Biodiversity.