You are looking at the Park Range of the Canadian Rockies. I was in McBride yesterday afternoon and when I walked out of the train station, this is what I saw; the yellow and green patches of the slope.
The yellow leaves are the Aspen, Birch, and Cottonwood trees, and the green patches are Douglas Fir, Spruce, and Balsam (Fir) trees.
The main reason so much of the slope is covered with deciduous (trees with leaves) is because back in around 1913 a forest fire swept through, destroying the original forest which was probably all conifer trees (trees with needles), and when the area grew back, the deciduous trees won the race. It has always been rumored that the original surveyors in the valley set the fire to make their surveying job easier.
It is probably a good thing that the slope is now covered with patches of both deciduous and conifer trees because leaved-trees don’t really burn well, and in case of a forest fire, they would hamper the progress of a fire, thus providing some protection to residents in the valley.
You can see my photo-realistic paintings at: davidmarchant2.ca