Is Calgary in a Grassland Biome?

No. Calgary, Alberta is located in the foothills of the Rocky Mountains and lies within the Boreal Forest biome (specifically the Aspen Parkland and Montane subregions), not the grassland biome.

The grassland biome (Prairie Ecozone) begins east of Calgary. The city sits at the transition zone where parkland—characterized by trembling aspen groves interspersed with fescue grasslands—meets the montane forests of the mountain foothills.