Fire is a common, recurrent, and integral component of many forest ecosystems. Prescribed fires are set for a number of reasons, including the reduction of brush competition, the elimination of advance regeneration, and the abatement of damage attributable to insects, pathogens and vertebrates. Fire causes changes in soil physical properties, soil microclimate, soil nutrient status, and soil biology. The occurrence of dwarf mistletoe, Arceuthobium spp., is influenced by fire. Damage attributable to Rhizina undulata Fr. is increased after prescribed burning. Damage caused by other pathogens may be decreased by removal of susceptible hosts. Fire affects vertebrates primarily by alterations to food and cover. Vertebrate pests often favour the site and vegetational characteristics created by fires. Populations of insects resident in slash may be temporarily reduced by prescribed burning. Underburning shows promise for direct control of seed and cone insects in seed production areas, and for elimination of understory trees which promote survival of western spruce budworm, Choristoneura occidentalis Freeman. Fire should be used in wilderness areas, where appropriate, to maintain pre-suppression stand structures and minimize risk to forest pests. (Abstract shortened by UMI.).
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机译：火灾是许多森林生态系统的常见，反复发生的组成部分。造成火灾的原因有很多，包括减少电刷竞争，消除提前再生以及减轻可归因于昆虫，病原体和脊椎动物的损害。火灾引起土壤物理性质，土壤微气候，土壤养分状况和土壤生物学的变化。矮小槲寄生Arceuthobium spp。的发生受到火的影响。可归因于Rhizina undulataFr。在规定的燃烧后增加。通过去除易感宿主，可以减少其他病原体造成的损害。火主要通过改变食物和遮盖物来影响脊椎动物。脊椎动物害虫通常偏爱大火造成的地点和植被特征。可以通过规定的焚烧方法暂时减少生活在斜线中的昆虫种群。欠燃表明有希望直接控制种子生产区的种子和锥虫，并消除能促进西部云杉芽虫Choristoneura occidentalis Freeman存活的林下树木。应在荒野地区适当使用火源，以维持林分结构的预先抑制并使对森林有害生物的风险降至最低。 （摘要由UMI缩短。）。
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