The spruce budworm (SBW) is the insect defoliator responsible for the greatest tree mortality in North America. Fragmentation and loss of habitat are expected to affect the movement of SBW through forested landscapes during periods of dispersal thereby modifying outbreak severity and frequency.

中文翻译：

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栖息地丧失和景观破碎化导致云杉芽虫爆发的不可预测性增加

云杉芽虫 (SBW) 是导致北美树木死亡率最高的落叶昆虫。栖息地的破碎化和丧失预计将影响SBW在扩散期间在森林景观中的移动，从而改变爆发的严重程度和频率。