I have evergreen conifers that I am planning to train once dormant. I live in Southern California in zone 10. It's indeed pretty warm here. Our winters are not very cold. Due to climate change, we still get warm temperatures in December in the 80s F (26-30 C). As we know, most conifers are very hardy. So would they respond to the seasons in Southern California? Is there a way to tell if an evergreen is dormant in zone 10?
These are just examples. Like with Spruce, there's colorado blue, norway, oriental, black hills, and more; and their hardiness zones aren't all the same. For Zone 10, apparently cypress, Himalayan Spruce, some junipers, some cedars will be successful.
(Sorry, this doesn't specifically answer your question, but maybe some of this information might give you insight. I know some conifers deal with drought pretty well, and socal has some Pines like Torrey Pines. I am not sure if Ponderosa Pines do. I am also not knowledge in determining dormancy.)