The Mexican Cypress, native from Mexico to Honduras but planted widely and naturalized. Photo from the Santa Marta Mountains of northeastern Colombia. In context at www.dixpix.ca/meso_america/Flora/primitive/index.html
A huge 50'ft tall,3 foot diameter Arizona Smooth Bark Cypress(Cupressus glabra) in Zion. I think it is likely cultivated since it was in the campground, but could it get that big in 100 years or so?