High end log cabins with sod roofs are making a comeback in Alberta. Their earthen design are environmentally friendly, attractive, and energy saving. Green roofs (living roofs) are certainly more common in Europe than in Canada, though they are slowly starting to creep their way into this country (check out the roof on MEC in Toronto).
A sod roof would have been the only option used by the NWMP when they arrived on the prairies… given the lack of building materials and the urgent need for protection from the summer heat and the winter cold. It looks like the grass on the roof of the building above is prairie grass. In the harshness of the Alberta climate it’s hard to keep anything else alive without constant care.
Goats are on site to help mow the roof. However, it seems they preferred to eat the grass and food pellets provided by La Niña.