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Most of the leaves in Saskatchewan have now fallen, after gusting winds and wintry weather rolled through the province over the past week.
But this autumn, the red, orange and yellow canopy held on longer than in other years. Long-time Saskatchewan photographer John Perret has noticed a distinct difference.
“This year has been a little different in terms of the weather, so they went on for quite a while until the 90-kilometre winds hit [last] weekend,” he said.
Photographer John Perret has noticed a delay in the peak of fall colours in Saskatchewan, which often occurs in late September and October. (Submitted by John Perret)
Perret, who is based in Saskatoon, has been capturing fall landscapes in the province for years. While the foliage can vary from season to season, he said fall leaf colours often peak in late September and the first couple weeks of October.
But this year, the leaves held on longer in Saskatchewan, still displaying hues of orange and yellow during the latter half of October. In a few cases, some trees were still in full leaf on Oct. 28, despite recent winds and snow.
Landscape photographer John Perret has photographed landscapes for decades, and noticed the fall leaves have held on much longer this season. (Travis Reddaway/CBC)
Why did leaves hang on longer?
Raju Soolanayakanahally, a research scientist at Agriculture and Agri-Food Canada, confirmed leaves held on longer this year and said it’s not exclusive to Saskatchewan.
“Definitely this year we are seeing an extended leaf retention on most of the Prairie or across Canada,” he said.
Until the recent winds and snow, leaves were hanging onto Saskatchewan trees longer than normal this fall. One research scientist says it happened across much of Canada this fall, thanks in part to El Niño.
“The leaves are staying on trees for much longer.”
Soolanayakanahally said the ongoing development of the so-called super El Niño along the equatorial waters in the Pacific Ocean is part of the reason.
Photographer John Perret says that on top of fall leaves peaking later this season, their vibrancy was diminished compared to previous years. (Submitted by John Perret)
“Warm oceans in [the Pacific] have created the warmth where the night temperatures are not going to the killing frost. So the leaves are staying on the trees for much longer,” he said.
“That has allowed for that gradual fall colour to creep in, whether we see the fall colours in the form of yellow on aspens, to carrot colours or the red colours.”
The science behind leaf change
In the spring and summer months, the chemical chlorophyll absorbs red and blue light from the sun to power the process of photosynthesis. This produces a green pigment in leaves.
As shorter and cooler days arrive in the fall, chlorophyll production stops as the tree prepares for winter, Soolanayakanahally said.
“During this phase the green pigment — what we call chlorophyll — it breaks down. And it makes the other pigments such as carotenoids,” he said. “The yellow pigment is given by xanthophylls, and the carrot pigment is given by beta carotene. They become prominent.”
Once chlorophyll production stops, leaves lose their green pigment and showcase red, orange and yellow pigments from other chemicals. (CBC)
While weather can dictate when leaves drop each season, it can also determine how vibrant the colours are.
Fall leaves are often more vibrant when the end of summer is dry and the fall is sunny, with nights free of killing frosts.
Perret — who has also photographed sought-after fall colours in New England — said Saskatchewan’s unique landscapes and vibrant colours make for beautiful scenes.
“There’s nothing better than getting out in the fall in the warm weather and taking photographs,” he said.
“Even if you’re not taking pictures — just go for a walk and enjoy the colours and everything else that fall has to offer.”
