Alberta, Manitoba, and Saskatchewan are known as Canada’s prairie provinces. The Canadian prairies extend far into the United States. The combined land area of prairies in both countries added together exceed over 3,000,000 square kilometers. The prairies of Central Canada and those of the United States were created as a result of a rain shadow cast over the area by the formation of the Rocky Mountains. Moisture coming in from the Pacific fell west of the Rockies. The little rain falling on the eastern slope resulted in a vast stretch of grassland with limited trees. The prairies did receive enough precipitation to sustain the various grasses feeding the growing herds of bison. Several Native American tribes built a dependent relationship on the bison herds as a source for food, clothing, and shelter.
