What is Up with Leaves Falling Already in August?

August 18, 2023August 18, 2023 Top Quality Canada

If you live in the Greater Toronto Area, you have certainly noticed that leaves started to discolour and started to fall off. Something that is known to happen only in September and October but not beginning and mid of August! Why is this happening?

Ontario has seen unusual rainy and bellow ordinary temperatures in recent weeks. Toronto for instance has received 13 rainy days in June and staggering 18 during month of July. Not really a perfect and hot summer everyone has hoped for. But the temperatures really plummeted beginning of August. Toronto and many other towns in the GTA have had night temperatures dropping down to 10 degrees celsius only. making fall season knocking on the door early this year.

But Ontario is not the only recipient of unusual cold weather.

Western Canada saw a record-breaking wildfire season, which could have caused the region’s weather to quickly change from scorching heat to bitter cold.
In some of the highest elevations, unusually significant snowfall of about 2 feet hit areas of Alberta and British Columbia. The area that had been devastated by fire needed the sudden downpour of wintry precipitation badly.

Causes for early Fall

Ontario, Canada: leaves start to discolour and change color earlier than expected, often as early as August. This early onset of leaf discolouration, also known as leaf senescence, has puzzled residents and visitors alike. We will delve into the underlying reasons for this fascinating phenomenon and explores the multitude of factors contributing to the premature shift in fall foliage.

1. Day Length and Photoperiod:

One of the primary triggers for leaf senescence is the gradual decrease in daylight hours as summer wanes and autumn approaches. This decrease in photoperiod serves as a biological signal for deciduous trees to begin preparing for the upcoming winter months. In southern Ontario, the latitude leads to a notable reduction in daylight hours as early as August, setting in motion the cascading physiological changes that result in leaf discoloration.

2. Temperature Fluctuations:

Another critical factor contributing to early leaf discolouration is the fluctuating temperature patterns characteristic of late summer and early fall. Southern Ontario experiences variations in temperature during these transitional months. Warm days followed by cooler nights can accelerate the breakdown of chlorophyll, the pigment responsible for the green color of leaves, and uncover other pigments that create the vibrant reds, oranges, and yellows associated with autumn foliage.

3. Drought Stress:

In some years, drought conditions can exacerbate the early leaf discolouration. Insufficient moisture in the soil can lead to water stress for trees, affecting their ability to maintain healthy leaves. When trees experience water stress, they may accelerate the senescence process to conserve resources and energy, resulting in the premature shedding of leaves.

4. Natural Variation:

It’s important to note that the timing of leaf senescence can vary from year to year and even from tree to tree. This natural variation is influenced by a combination of genetic factors, environmental conditions, and the overall health of individual trees. Some species are naturally predisposed to turn color earlier in the season, while others may hold onto their green leaves for longer.

5. Invasive Species and Climate Change:

The introduction of invasive species and the effects of climate change can also play a role in altering the timing of leaf senescence. Invasive insects or pathogens can weaken trees and accelerate the process of leaf discolouration. Additionally, warming temperatures as a result of climate change can disrupt the delicate balance between day length and temperature cues, leading to shifts in the timing of seasonal changes.

Fall maintenance — Property fall cleaning

Does this change in seasonal dates mean we have to clean leaves earlier this year? Unfortunately, yes. Leaves have started to fall already and many properties have to be cleaned earlier than expected.

Let’t only hope we will not have an extreme cold winter this year.