From the Introduction: In the far north, snow and ice have a firm grip on the land for the better part of the year. The summers are short and plant growth usually is sparse. This boreal forest valley at least is located far enough south to allow for a few trees to grow. Only recently have the days become long enough to melt most of the snow from the tree’s branches. But the nights are still long and cold enough to freeze the melt water on the slopes of the hills and in the little stream at the center of the valley. This makes the slopes slippery and tricky to climb long after sunrise and again long before sunset.