ezo spruce is very closely related to sitka spruce ("picea sitchensis"), which replaces it on the opposite side of the north pacific. they, particularly subsp. "jezoensis", can be difficult to distinguish, with the absence of stomata on the upper surface of the leaves of "p. jezoensis" being the best feature. its leaves are also somewhat blunter, less sharply spine-tipped, than sitka spruce.