Understanding the complexity of forest community dynamics is essential in forest management planning and stewardship, yet lowland northern white-cedar (Thuja occidentalis L.) are often managed as homogenous communities. Through this study, we defined lowland white-cedar forest community types in unharvested and harvested forest stands within the State of Michigan and examined community type associations with ecological variables. Data collected in unharvested stands revealed three white-cedar community subtypes: (1) cedar-deciduous, (2) cedar-conifer, and (3) cedar-shrub. These unharvested subtypes were dominated by white-cedar, yet characterized by different soils, hydrology, geochemical gradients, and associated tree species. In harvested stands, six community types were identified: (1) aspen-fir, (2) winterberry-willow, (3) balsam fir, (4) cedar-red maple, (5) cedar-black spruce, and (6) alder-tamarack. These harvested community types were located along ecological gradients, including soil type (organic or mineral) and soil water pH. Using community types in unharvested and harvested stands, and associated ecological gradients, potential pathways of compositional transition were theorized. Findings suggest that cedar community subtype affects the likelihood of cedar regeneration and dictates the alternative species replacing cedar after harvest. These findings and potential pathways are useful to forestry practitioners, as they highlight potential changes in tree species dominance following harvest across a range of lowland white-cedar community types, allowing refinement of silvicultural prescriptions to ensure desired outcomes.

了解森林群落动态的复杂性对于森林管理规划和管理至关重要，但低地北部白雪松 ( Thuja occidentalis L.) 通常作为同质群落进行管理。通过这项研究，我们定义了密歇根州未采伐和采伐林分中的低地白雪松森林群落类型，并研究了群落类型与生态变量的关联。在未采伐的林地中收集的数据揭示了三种白雪松群落亚型：（1）落叶雪松，（2）雪松针叶树和（3）雪松灌木。这些未采伐的亚型以白雪松为主，但具有不同的土壤、水文、地球化学梯度和相关树种的特征。在采伐林中，确定了六种群落类型：(1) 白杨-冷杉、(2) 冬莓-柳树、(3) 香脂冷杉、(4) 雪松-红枫、(5) 雪松-黑云杉和 (6)桤木落叶松。这些收获的群落类型沿着生态梯度分布，包括土壤类型（有机或矿物质）和土壤水 pH 值。利用未采伐和采伐林分中的群落类型以及相关的生态梯度，对成分转变的潜在途径进行了理论分析。研究结果表明，雪松群落亚型影响雪松再生的可能性，并决定了采伐后替代雪松的替代物种。这些发现和潜在途径对林业从业者很有用，因为它们强调了一系列低地白雪松群落类型收获后树种优势的潜在变化，从而可以改进造林方案以确保预期的结果。