The following was received via email: Here is my inquiry: Why can a palm tree and blue spruce grow side by side in Instanbul, but not at the same latitude in America? ---Upper Elementary teacher, Mrs. Nicolson
Well if we follow the 41st parallel from Istanbul through the US we see that it goes through PA, OH, just north of Denver and through CA. Many factors influence climate other than latitude - prevailing winds and altitude for example. Here in Vancouver, far north of Denver, those two plants will grow because our climate is moderated by warmth blown in from the ocean, but in Denver only the hardier blue spruce would survive.
They can be grown side by side in Britain, too. I'm sure there's also places at 41°N in Calif where the two can be grown together - close to the western edge of a continent, near an ocean or large sea (the Mediterranean Sea in the case of Istanbul), the summers are cooler (which is what Blue Spruce needs) and the winters are warmer (which is what palms need), so their requirements overlap. In the interior and east of continents, the winters are colder and the summers hotter, making their requirements move far away from each other Having said all that, I don't recollect seeing any Blue Spruce in Istanbul when I've been there