The Larch Casebearer and Its Host Tree:: I. Population Dynamics of the Larch Casebearer (Coleophora Laricella Hbn.) from Latent to Outbreak Density in the Field. Habermann, M. 136(1-3):11–22.
The Larch Casebearer and Its Host Tree:: I. Population Dynamics of the Larch Casebearer (Coleophora Laricella Hbn.) from Latent to Outbreak Density in the Field [link]Paper  doi  abstract   bibtex   
The population changes of two larch casebearer (Coleophora laricella Hbn.) populations were analysed under field conditions from 1991 to 1995 using a differential analysis: one insect species feeding at the same time on two needle types (spurshoot and longshoot needles) of two host species (European and Japanese Larch) under two different environments (Solling hills: resource-rich stand, lowlands: resource-poor stand). Casebearer density in the lowlands was always significantly lower than in the Solling hills. The main factors regulating casebearer density were obviously the same for both populations, although feeding intensity and environmental conditions differed. The most important factors influencing density changes were the mortality of the mining young larvae and, to a lesser degree, the hibernation and spring mortality of the L3/L4 larvae. The rates of pupal parasitism were low in the Solling hills (max. 8.7%) although density was much higher than in the lowlands where pupal parasitism was higher (max. 18.5%). There was no evidence for regulative effects of parasites or predators in both populations. It is supposed that larval mortality mainly depends on needle physiology, which in turn is supposed to be influenced by environmental conditions. Different environmental conditions seemed to determine the feeding tolerance levels of the infested host trees. Therefore, Larch trees growing under optimal conditions may be able to tolerate periodical defoliation by the casebearer but Larch trees growing under suboptimal conditions may have to reduce the risk of defoliation to a sustainable degree.
@article{habermannLarchCasebearerIts2000,
  title = {The Larch Casebearer and Its Host Tree:: {{I}}. {{Population}} Dynamics of the Larch Casebearer ({{Coleophora}} Laricella {{Hbn}}.) from Latent to Outbreak Density in the Field},
  author = {Habermann, Michael},
  date = {2000-10},
  journaltitle = {Forest Ecology and Management},
  volume = {136},
  pages = {11--22},
  issn = {0378-1127},
  doi = {10.1016/s0378-1127(99)00266-2},
  url = {https://doi.org/10.1016/s0378-1127(99)00266-2},
  abstract = {The population changes of two larch casebearer (Coleophora laricella Hbn.) populations were analysed under field conditions from 1991 to 1995 using a differential analysis: one insect species feeding at the same time on two needle types (spurshoot and longshoot needles) of two host species (European and Japanese Larch) under two different environments (Solling hills: resource-rich stand, lowlands: resource-poor stand). Casebearer density in the lowlands was always significantly lower than in the Solling hills. The main factors regulating casebearer density were obviously the same for both populations, although feeding intensity and environmental conditions differed. The most important factors influencing density changes were the mortality of the mining young larvae and, to a lesser degree, the hibernation and spring mortality of the L3/L4 larvae. The rates of pupal parasitism were low in the Solling hills (max. 8.7\%) although density was much higher than in the lowlands where pupal parasitism was higher (max. 18.5\%). There was no evidence for regulative effects of parasites or predators in both populations. It is supposed that larval mortality mainly depends on needle physiology, which in turn is supposed to be influenced by environmental conditions. Different environmental conditions seemed to determine the feeding tolerance levels of the infested host trees. Therefore, Larch trees growing under optimal conditions may be able to tolerate periodical defoliation by the casebearer but Larch trees growing under suboptimal conditions may have to reduce the risk of defoliation to a sustainable degree.},
  keywords = {*imported-from-citeulike-INRMM,~INRMM-MiD:c-13523129,coleophora-laricella,forest-pests,larix-decidua},
  number = {1-3}
}
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