Canadians in this part of the country are familiar with how the colours of leaves change from their summer greenery to a vibrant palette of reds and yellows.
The foliage of the maples, dogwoods, birches, oaks, beeches and other trees and shrubs begin this process towards the end of September and continue into October. Almost all of these plants are deciduous and broad-leafed, although some conifers, such as larches, turn colour, too.
You may see advertisements for tours into some regions of the east where colours are most vivid. You can drive yourself or take buses along such routes through the Kawarthas, Algonquin Park, the Eastern Townships of Quebec and New England, where autumn colours are best seen. Readers in the Fall 2019 CAA magazine are advised to “take the scenic route” in Northumberland County and enjoy the autumnal colours and other sights there.
he shortening days and cooler temperatures trigger the deciduous plants to drop their leaves. A layer of cork-like cells builds up at the base of each leaf stem, halting the flow of nutrients between leaf and tree. As the manufacture of chlorophyll ceases and its green colour fades, the carotin and xanthrophull, a yellow photosynthetic pigment, are exposed, turning the leaves yellow. Before the sugars or tannins, which occur for protection against predators, drain away from a leaf, a red pigment is produced, resulting in the red or crimson colours.
There is a sequence of colours to be seen and observing the changes in the trees around Brantford and Brant County can give one a reasonable schedule. The yellow leaves of the white canoe birches are one of the first heralds of autumn. Another early tree is the red maple (Acer rubrum), of which there are a few planted along our streets. The serviceberry can display yellows, oranges and reds but such trees are perhaps more usually seen in “cottage country.”
Next are trees less commonly planted here, namely sourwood and sweet gum, both red, while about the same time the ginkgos turn yellow. You can see a few in Brantford’s parks. By the third week, you should see the European beech turn yellow along with the tulip tree and the eastern redbud. This is the time for the sugar maples to flaunt their orange and yellow leaves. The Norway maple has been planted widely and is noted for its bright yellow leaves. Later the oaks come into their own. The scarlet oak certainly has the brightest colour; the other oaks less so.
A few other trees and shrubs noted for their fall leaf colours are Ohio buckeye, the alders and the hawthorns, the ashes where any still exist, witch hazel, oak leaved hydrangea, golden rain tree, magnolias, crab apples, poplars and the willows. One should not overlook fall fruit, which can be striking. Some examples are on chokeberry, northern catalpa, the dogwoods, common witch hazel, most roses, mountain ash, Virginia creeper, yew and snowberry.
In the forests leaves have been falling from the deciduous trees for a long long time and when they decay are incorporated into the soil contributing to its fertility. You can do the same thing by collecting the leaves for your compost pile or simply by setting them out in the proper bags for the municipality to compost.
Denzil Sawyer is a freelance writer and Master Gardener.