They need an especially wide planting strip. Destructive to paving, roots heave sidewalks. They are susceptible to anthracnose diseases. Crownright' is a variety that should be used to avoid this problem. In Seattle, it is highly susceptible to canker attack, which is often fatal.
American elm is highly vulnerable to Dutch elm disease.
This disease is expected to kill the elms in this area. Newer disease resistant varieties may be approved for street planting. Chinese and Siberian elms have brittle wood, and are prone to storm damage. Conifer trees are not generally recommended for street planting. They may be approved for street planting if the site is deemed appropriate.