If you are under the impression that the softwood forest is even all along your hike, you are wrong. Vegetation changes when you climb. So, from the bottom of the mountain to the summit, you can cross a fir zone with yellow birch, then another fir zone with silver birch and, finally, white spruce. At last, you will arrive to the tundra after crossing a scraggy tree forest, called krummkolz. This spectacular variation is caused by the climate which changes as you go up the mountain.
One can find in certain sectors of the Trail, the largest area of Tundra in Southern Quebec, situated on the highest summits as high as 1 100 metres high. The vegetation can be compared to what is found in Quebec's Far North, well adapted to severe cold, wind and snow.
The tundra landscape is a stark and barren place. The plants growing in the tundra are often small and grow close to the ground. During the short-growing season in the summer, the tundra blooms with a variety of plants. One has to bend down in order to see them. During the brief summers, the top section of the soil may thaw just long enough to allow plants and micro-organisms to grow and reproduce. Some varieties will be called alpine-arctic, that is to say, typical plants of the arctic environment and high mountains.
These plants must face really difficult conditions: short summers, temperatures below freezing even in July, constant winds, a limited number of sunny days, high precipitation rate... Such conditions are the cause for which only adapted or acclimatized vegetation will settle, such as lichen, a cross between fungus and algae.
Some plants are able to survive in the tundra because of their genes. They are actually transmitted from one generation to the next, as in arctic-alpine vegetation. An acclimatized plant is one which modifies itself in order to be able to survive within harsh conditions by developing non hereditary genes, as with boreal plants found on mountain summits. Arctic-alpine flowering vegetation blossoms early, about one month after the thaw comes for a variety of species.
The tundra is not a plant's best place to grow because permafrost that is about a finger-length under the surface in the summer months prevents the plants' roots from growing as long as they need.