Effectiveness of insecticides, physical barriers and size of planting stock against damage by the pine weevil (Hylobius abietis)

Abstract

Effectiveness of insecticides, physical barriers and size of planting stock against damage by the pine weevil (Hylobius abietis). Crop Protection . p. 105307.

Acetamiprid, chlorantraniliprole, and in some situations the physical barriers MultiPro® or Kvaae® wax, can be alternatives to traditional synthetic pyrethroid insecticides for the protection of young conifers from damage by the large pine weevil Hylobius abietis L.

“…The experiments reported here confirm the efficacy of acetamiprid as part of the integrated pest management of Hylobius, supporting evidence from elsewhere (Hardy et al 2020;Willoughby et al 2020;Moore et al in prep). Our results indicate that pre-treating trees with 0.037 g a.i.…”

“…stem −1 chlorantraniliprole is likely to be required in the spring of the second year after planting. Hardy et al (2020) also reported promising levels of protection over two years, similar to that provided by acetamiprid, for 0.013 g a.i. stem −1 chlorantraniliprole, which is the maximum application rate currently permitted for pre-treatment applications in the UK, assuming a standard post-treatment planting density of 2700 stems ha −1 (Health and Safety Executive 2019).…”

“…Alternatively, it is possible that the Hylobius population levels on the sites where trials were conducted may have been lower in Scandinavia than in the UK. In contrast, Hardy et al (2020) reported that on three intermediate to high population sites in the UK, MultiPro® guards gave adequate protection for two years, similar to that provided by a single applications of acetamiprid or chlorantraniliprole, although on two high population sites protection was inadequate.…”

“…Where failure of the MultiPro® barriers occurred in our work, it is likely to have been due to insects accessing the tree stems via gaps left between the base of the sleeves and the stem, or "bridging" caused by brash or vegetation providing access to the upper parts of the transplants where they emerge from the protective barriers. Other problems reported with some types of physical barrier sleeves are that they are difficult and time consuming to fit, particularly over larger plants with bigger branches; it is difficult to bury the lower part of the guards on stony or very friable soil correctly; guards can become dislodged and fail on exposed sites, which are common in upland forestry in the UK; they are between 3 and 20 times more costly than insecticide pre-treatment; and they may make subsequent top-up spraying, if required, prohibitively expensive to carry out (Hardy et al 2020;Willoughby et al 2020).…”

Comprehensive comparison of treatments for controlling the large pine weevil (Hylobius abietis) in Central Europe

“…The use of synthetic insecticides is effective and relatively cheap 24 . However, because of adverse environmental effects, insecticide use will be increasingly restricted 2,19,24,25,26 and replaced by various physical feeding barriers 27 .…”