Distribution of <i>Coleophora laricella</i> (Lepidoptera: Coleophoridae) and its major parasites in the crowns of western larch in British Columbia

Authors

  • Gordon E. Miller Simon Fraser University Burnaby, B.C.
  • Thelma Finlayson Simon Fraser University Burnaby, B.C.

Keywords:

<i>Coleophora laricella</i>, Lepidoptera, Coleophoridae

Abstract

The distribution of <i>Coleophora laricella</i> (Hbn.) and its parasites <i>Dicladocerus</i> spp. (<i>D nearcticus</i> Yosh. and <i>D. pacificus</i> Yosh. (Yoshimoto 1976)) and <i>Spilochalcis albifrons</i> (Walsh) in the crowns of western larch were determined for five classes of trees. In open-grown trees more than 7.6 m high, <i>C. laricella</i> densities were greater at 1.5-3.1 m than at 6.1-7.6 m above the ground, on the sunny side of a tree than on the shaded side, and on the outer half than on the inner half of a branch. In open-grown trees 3.0-4.6 m high and in trees forming a closed canopy, only the outer branch halves had significantly greater densities. The only significant variation in parasitism by <i>Dicladocerus</i> spp. occurred between branch halves in open-grown, non- roadside trees more than 7.6 m high, with more parasitism on the inner halves than the outer. Parasitism by <i>S. albifrons</i> was significantly greater at the lower crown level than at the higher in open-grown, closed-canopy, non-roadside trees that were more than 7.6 m high, and on the outer branch half than on the inner half in the same category of tree.

References

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Published

2019-08-28