Black spruce (Picea mariana [Mill.] B.S.P.) and white spruce (Picea glauca [Moench] Voss.) are congeneric species. Both are moderately shade tolerant and widely distributed across North American boreal forests.

中文翻译：

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北方针叶树的CO ₂刺激和响应机制随光的供应而变化

黑云杉（Picea mariana [Mill。] BSP）和白云杉（Picea glauca [Moench] Voss。）是同类。两者均具有中等的耐荫性，并广泛分布于北美北方森林中。