In Canada east of the Rocky Mountains, tundra and boreal forest run across the country from the mountains to the Atlantic Ocean. South of the boreal forest, there are grasslands in the Prairie Provinces, and deciduous forests in the east. Only climate can explain the extent of each zone. In Saskatchewan, the relationship between precipitation and temperature is critical. As a rough rule, forests grow where the rate of precipitation exceeds the rate of evaporation.
Higher temperature means a higher rate of evaporation.
Precipitation doesn't change much from north to south in Saskatchewan, but temperature does. There are forests in northern Saskatchewan because it is cooler there than in the south, not because of more rain and snow. There is a delicate balance between temperature and precipitation in Saskatchewan. Global warming is a very real threat to the province because it could easily upset this balance. The Parkland Ecoregion in which Redberry Lake lies is usually regarded as part of the Grassland Vegetation Zone or Prairie Ecozone, but it is actually a transition from grassland to forest.