The many colours of fall

The countdown to fall has begun; children are returning to school, sweaters and long pants are reappearing and birds and butterflies are beginning their migratory journeys.  Some of us experience a kind of grieving at this time of year; we mourn for the long hot days of summer.  But others celebrate fall – a time of glorious colour, quiet parks and few bugs.

Only a few regions of the world offer the kind of spectacular, showy fall colours that Ontario is famous for. The climate and deciduous trees of Northeastern North America provide the perfect storm for transforming our lush green foliage into the brilliant reds, yellows and oranges.


Have you ever wondered why leaves change colour in the fall?

Do you remember learning about photosynthesis in school?  Very simply, it’s the process where plants take energy from the sun and turn it into food.  Chlorophyll molecules, coloured green, are critical to this process.  But chlorophyll is a tricky thing – it continually breaks down and is recreated, fueled by sunlight and warm temperatures.  Come fall, this process slows, the intensity of the green fades, and other colours emerge.

Why do some leaves turn red and others yellow?

As well as chlorophyll, two other components are important to leaf colour – carotene and anthocyanins.  Carotene is more stable than chlorophyll – so when chlorophyll has disappeared carotene stays around causing leaves to appear yellow.  But not all fall leaves are yellow.  In some trees a concentration of sugars causes anthocyanins to form.  These pigment compounds cause leaves to turn red.

The brilliance of fall colours is greatly influenced by the weather. Low temperatures but above freezing destroy chlorophyll and promote the formation of anthocyanins.  Dry weather increases the sugar concentration in sap and also increases the amount of anthocyanin. So the best fall colours are produced when dry, sunny days are followed by cool, dry nights.


When will colour peak?

Ontario Parks staff are reporting regularly on leaf change across the province.  Check out our Fall Colour Report for the latest updates.

Fall Vantage Points

Ontario Parks has some great vantage points to see colours at their peak:

Algonquin is world-famous for its fall colour.  Hike the Track and Tower Trail, a 7.7km looped trail, for views over Cache Lake.  Located off of Hwy 60 at km 25.

Awenda is located north of Midland, and includes the Nipissing Bluffs (almost 60m). They are the remains of an ancient shoreline, and provide an excellent perch to see fall colours. The park has over 30 km of trails, but the best one for fall colour viewing can also be cycled. The 13km Awenda Bluff Trail is not too strenuous. It’s a great fall outing – with spectacular views of Georgian Bay including Giant’s Tomb.

Sleeping Giant is a long peninsula that juts out into Lake Superior, one hour southeast of Thunder Bay. Stunning park scenery includes cliffs reaching heights of 240 metres. Panoramic views of Lake Superior are unforgettable.

Restoule is about sixty-five kilometres southeast of North Bay. This park has an extensive hikig trail network that crests several scenic lookouts. Fire Tower Trail takes you one hundred metres above Stormy Lake and offers spectacular views westward towards the French River.

Killbear is one of Ontario’s busiest provincial parks, but come fall its sandy beaches and granite rocks are less crowded making this park a fabulous choice for a fall camping trip. The 3.5 kilometre Lookout Point Trail has a breathtaking view of Georgian Bay. A trail guide explains the ecology of the area.

Charleston Lake Provincial Park is northeast of Kingston. A great fall hiking destination, this park was first inhabited by native peoples. It became a destination for wealthy cottagers in the early 1900s. The new Blue Mountain Trail can be up to ten kilometres long depending on your route. It takes you to the highest point of land in eastern Ontario.

Samuel de Champlain is easy to access from the Trans-Canada Highway east of North Bay. Day use hiking trails in this park include the Red Pine Trail, which has two lookouts with sweeping views of the Mattawa River Valley’s fall colours.

Intrepid hikers will want to climb to the top of The Crack at Killarney.   At the top, hikers will be rewarded with panoramic views of fall colours set dramatically against the white quartzite of the LaCloche Mountain.