This is the classic winter picture of a boreal forest, or taiga. This habitat exists only on subpolar latitudes, where the climate is too extreme for broad-leaved angiosperms to take root, thus making the taiga an exclusive conifers-only club.
In an alternate Earth, there is a clear ecological distinction between the two types of trees. Broad-leaved angiosperms lord over the lowlands whereas conifers can be found only on the cooler, drier and rockier highlands. So where does that leave the taiga?
In this same alternate Earth, the boreal forest consists primarily not of conifers, but a kind of grass called bamboo.
Now in order to survive in a latitude where the summers are short and the winters bitterly cold, these boreal bamboos may have to grow more slowly--like, instead of six weeks to reach the maximum height of 100 feet, it happens in six years. Is this change in adaptation enough for bamboo forests to thrive in subpolar latitudes, or should more changes in characteristics be required?