top of page

ASK US WHY - OCTOBER 5, 2023


A reader has been looking up, way up, at the trees and they noticed that some of the trees are not like the others. So, they did what engaged readers do (hint, hint), they asked us why some trees already “look dead but are surrounded by summer-lush greenery.” They also wanted to know why “the same tree species don’t seem to turn colour at the time during the season.”

The Third reached out to Joe Barrie, the owner of Air-Ex in North Sydney for the answers. He says that he has been noticing the exact same thing. “I turned the corner [the other day] and all that stood out was this flame orange maple tree,” he said. “The other trees around it for hundreds of meters we're still completely green.”

Barrie says there are three main reasons why tree leaves change colour before dropping to the ground.

“Basically, when a tree reacts to a season it is caused mainly by cell deterioration as well as chlorophyll production slowing down in the leaf,” he said. “This can be determined by a multiple of things, like tree genetics; species reactions to cooler temperatures; as well as daylight hours.”

Genetics

Like animals, every tree is different, so genetics play a role in the colours we see. Barrie says it is normal for the same species of trees to change colours at different times because of factors such as the number of daylight hours it is getting. “But when you find individual trees that stand out because they're so ahead of the rest in changing colours. It is mostly genetics,” he said.

Daylight hours

Some trees are more sensitive to the amount of daylight they get per day. Remember, the shorter the days, the less chlorophyll produced in the leaf to keep it that green colour.

The fall colors we are about to start seeing everywhere in the Third are always present in the leaves, but the chlorophyll keeps them from showing. “When the production of the chlorophyll starts slowing down the leaves start slowly changing colors,” he said. “The leaves will show their brightest colours when the chlorophyll in the leaves is completely dead.”

The Colder Temperatures

The other big effect on the colour of our leaves is the temperature. The cold will cause the chlorophyll in the leaves to start to slowly die off. “Again, it's all in the genetics. Some trees of the same species might turn color before the others simply because it's not as resilient to the cold as the other trees,” he said. “They're all different. And very beautiful.”

Barrie says that a tree and its branches can change colours at different times during the season. He tells The Third that although some people think that a tree is unhealthy if some parts of it turn before others, that is not the case. “Trees are kind of like people when it comes to the cold,” he said. “Some trees really don't like the cold and would love to be living somewhere warmer, while others don't feel the effects at all until the temperature gets more severe.”



Genes, sun, and temps. But genetics are responsible for those lonely dead-looking ones as well as those solo flame orange Maples like Barrie saw last week.

There you have it.

The tree-hugging Thirder has a message for us as those leaves change. “There's nothing like going for a drive in Cape Breton in the fall. I hope whoever is able can get themselves out for a drive. Go for a walk. The fresh air is great, and this is the best time of the year for scenery as far as trees go.”


13 views0 comments

Recent Posts

See All

Comments


bottom of page