

- It does not occur because of frost. But, frost can disrupt the speed at which the leaves turn and halt colour transformation. Frost call kill the leaf and turn it brown.
Spring & Summer: trees are growing and turning green.
Fall: growth slows because of moisture levels, temperature, amount of stored energy in the roots, genetics. Systems begin to shut down as the tree prepares for winter dormancy
September 23rd (autumnal equinox): Days and nights are of equal length and thereafter the days are shorter and shorter. The sun's rays also become less direct and the air is cooler.
Autumn colour is a phenomenon that takes place within the leaves of a tree. Here's what happens:
- The lifelines between the leaves and the tree become blocked and the production of chlorophyll stops. The existing chlorophyll in the leaves slowly disappears as it is destroyed by sunlight.
- Throughout the summer, the green chlorophyll has been dormant, blocking out the other pigments, thus giving the leaves their green colour. Once the production of chlorophyll is halted, the leaves begin to show their true colours.
- As chlorophyll production ceases, other pigments become more dominant. Carotin helps with the orange colours and xanthrophyll is the yellow pigment.
- The leaves continue to change colour and reach their peak until the time just before the leaves fall. At the location where the leaf stem joins the branchof the tree, there is a separation layer. This is a layer of cells which gradually weaken, eventually causing the leaf to break off and fall.

- Colour change occurs on broad-leaved trees such as maple, oak, ash, and birch.
- These trees are also called "hardwoods" because most of them have wood which is quite hard, and "deciduous" because their leaves are shed each autumn.
- Trees that stay green all winter are "evergreen" or "coniferous" trees such as pine, spruce, hemlock, balsam, and cedar.
- Shedding their leaves actually protects the tree during winter. The leaves don't give off water (or transpire) when they are not on the tree, thus saving the tree from having the replace that water to keep the leaf alive.
Where in Muskoka is your favourite display of colour this year?


The sap of evergreen acts like an anti-freeze allowing their needles to survive throughout the long winter season. The nice smell when you crush the needles is the oil beneath their surface that allows them to survive. The needles also have a think wax coating allowing moisture to stay in.
Animals create many trail systems in the winter (like the deer trail above), connecting water, food and home locations. The trails allow for greater conservation of energy (which is key in the winter!). Moose and deer make trails based on shortest distance, as a result of their long narrow legs making traveling difficult in snow. Smaller animals on the other hand such as hares, skunks, and squirrels and even foxes make trails for both energy conservation and for survival; allowing them to swiftly escape their predators.