The City traditionally does a horrible job of planting and maintaining trees:
-planting them too late in the year (I know some people claim you can plant in the fall, but I always had far more success with planting in April and May)
-planting in locations where they are unlikely to survice (ex. west facing slopes, small vaults for street trees, too close to roads). The vaults that work for street trees in other cities don't work in Calgary. Planting too close to pavement or concrete also seems to decrease survivability in Calgary
-not providing wide enough boulevards and medians. Again, trees need more space to root in a dry climate with high temperature variability like Calgary
-not watering often enough for about the first 5 years
-siting too many in locations where they are likely to be hit my cars in the winter
The BP Birth Place forest program in the early 2000's seemed to do a great job of planting and maintaining trees - possibly something to emmulate.
Calgary trees already face many challeges and now the increased use of road salt in recent years seems to be taking its toll.
Before I left Calgary, my house backed directly onto Fish Creek Park. I had 9 trees on the lot plus probably 100+ bushes and junipers. It was high maintenance but looked great. The owner after me took great care of the yard, but the subsequent owner unfortunately removed most of the landscaping so the yard is little more than dead grass now
I question why someone uniterested in enjoying a yard would purchase a home like that.