<p>Urbanization can result in grassland- or cropland-dominated landcovers being converted into roads and buildings and sometimes planted tree cover. While planted trees in these urban settings may provide suitable habitat for tree-associated birds, they may not provide suitable habitat for the original grassland or cropland-associated species in the area. I examined habitat suitability of three tree-associated and three grassland-associated birds over three years (1870 [pre-European settlement], 1951 and 2021) in Regina, Saskatchewan Canada. Regina was historically in a treeless, grassland landscape, but has had an extensive tree planting program since 1913 resulting in over 500,000 trees currently planted within the city. Model-predicted mean habitat suitability for the three tree-associated birds increased from 0.04 in 1870 to 0.36 in 2021, whereas mean habitat suitability for three grassland-associated species decreased from 0.68 in 1870 to 0.45 in 2021. The model-predicted proportion of pixels within Regina that were deemed suitable habitat for tree-associated birds increased from 0 in 1870 to 0.11 in 2021 and for grassland-associated birds it decreased from 0.67 in 1870 to 0.35 in 2021. When city expansion occurs in grassland-dominated areas, city planners should avoid remaining patches of grassland habitat and when habitat restoration activities occur they should consider using landscape-appropriate plantings to ensure suitable habitat remains for grassland birds.</p>