Koopmans Jordan M, De La Giroday Honey-Marie C, Lindgren B Staffan, Aukema Brian H
University of Northern British Columbia, Prince George, British Columbia V2N 429, Canada.
Environ Entomol. 2009 Aug;38(4):1189-96. doi: 10.1603/022.038.0428.
The spatial influences of host and nonhost trees and shrubs on the colonization patterns of white pine weevil Pissodes strobi (Peck) were studied within a stand of planted interior hybrid spruce [Picea glauca (Moench) Voss x Picea engelmannii (Parry) ex Engelm.]. Planted spruce accounted for one third of all trees within the stand, whereas the remaining two thirds were comprised of early-successional nonhost vegetation, such as alder (Alnus spp.), paper birch (Betula papyrifera Marsh.), black cottonwood [Populus balsamifera ssp. trichocarpa (T. Ng.) Brayshaw], lodgepole pine [Pinus contorta (Dougl.) ex Loud.], trembling aspen (Populus tremuloides Michx), willow (Salix spp.), and Canadian buffaloberry [Shepherdia canadensis (L.) Nutt.]. Unlike the spruce trees, nonhost vegetation in the stand was not uniformly distributed. Spatial point process models showed that Canadian buffaloberry, paper birch, black cottonwoood, and trembling aspen had negative associations with damage caused by the weevil, even though the density of the insects' hosts in these areas did not change. Moreover, knowing the locations of these nonhost trees provided as much, or more, inference about the locations of weevil-attacked trees as knowing the locations of suitable or preferred host trees (i.e., those larger in size). Nonhost volatiles, the alteration of soil composition, and overstory shade are discussed as potential explanatory factors for the patterns observed. New research avenues are suggested to determine whether nonhost vegetation in early successional stands might be an additional tool in the management of these insects in commercially important forests.
在一片人工种植的内陆杂交云杉[白云杉（Moench）Voss×恩氏云杉（Parry）ex Engelm.]林分内，研究了寄主和非寄主树木及灌木对白松象甲（Pissodes strobi (Peck)）定殖模式的空间影响。人工种植的云杉占林分内所有树木的三分之一，而其余三分之二则由早期演替的非寄主植被组成，如桤木（Alnus spp.）、纸皮桦（Betula papyrifera Marsh.）、黑杨[香脂杨毛果杨亚种（T. Ng.）Brayshaw]、黑松[扭叶松（Dougl.）ex Loud.]、颤杨（Populus tremuloides Michx）、柳树（Salix spp.）和加拿大水牛果[加拿大水牛果（L.）Nutt.]。与云杉不同，林分内的非寄主植被分布并不均匀。空间点过程模型表明，加拿大水牛果、纸皮桦、黑杨和颤杨与象甲造成的损害呈负相关，尽管这些区域昆虫寄主的密度没有变化。此外，了解这些非寄主树木的位置，对于推断象甲侵害树木的位置所提供的信息，与了解合适或偏好的寄主树木（即那些较大的树木）的位置所提供的信息一样多，甚至更多。讨论了非寄主挥发物、土壤成分的改变和林冠遮荫作为观察到的模式的潜在解释因素。建议开展新的研究途径，以确定早期演替林分中的非寄主植被是否可能成为商业重要森林中这些昆虫管理的额外工具。
