Pine Weevil (pine + weevil)

Distribution by Scientific Domains

Kinds of Pine Weevil

  • large pine weevil


  • Selected Abstracts


    Effect of time of year on the development of immature stages of the Large Pine Weevil (Hylobius abietis L.) in stumps of Sitka spruce (Picea sitchensis Carr.) and influence of felling date on their growth, density and distribution

    JOURNAL OF APPLIED ENTOMOLOGY, Issue 3 2004
    R. Moore
    Abstract:, The time of year and time of felling of a commercial stand of Sitka spruce (Picea sitchensis Carr.) were both shown to influence the spatial distribution and development of the large pine weevil, Hylobius abietis (L). Stump and root systems were excavated over a 5-month period in 1997, between 18 and 27 months after felling, and all immature H. abietis removed. On a site with a 6-month spread of felling dates in 1995, mean larval weights in 1997 were higher in stumps from earlier fellings, but H. abietis numbers were higher in stumps from later fellings. This appeared to be due to the continued presence of older, heavier larvae, laid as eggs in 1995, in stumps from earlier fellings, combined with a greater concentration of oviposition having occurred in 1996 in the fresher stumps of later fellings. Pupae were first found in excavated stumps on 12 June 1997 and adults on 29 July 1997. Emergence of the ,new generation' of adult weevils commenced on 7 August 1997. On average, 25% of H. abietis adults emerged in autumn 1997, 41% in 1998 and 34% in 1999. First emergence (1997) was proportionally higher in the areas felled earlier in 1995 than those felled later that year. However, the opposite was found for third emergence (1999) where emergence was greater for stumps created later in 1995. Larger stumps contained greater densities of H. abietis. Total ,potential' emergence was estimated to be between 46400 and 170825 H. abietis/ha. However, emergence traps indicated that only 40,80% managed to complete their development and emerge successfully. It is suggested that within-season felling date may be one of the most important factors affecting larval development, distribution and abundance; as well as subsequent damage levels associated with adult feeding. Consequently, knowledge of felling date could be crucial to developing methods of integrated forest management for this major forest pest. [source]


    Feeding on roots in the humus layer by adult pine weevil, Hylobius abietis

    AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2006
    Kristina Wallertz
    Abstract 1,The consumption by adult pine weevil, Hylobius abietis, of the bark of roots present in the humus layer was assessed in a field study conducted in southern Sweden during two years (1998 and 2002). The study sites were divided into two areas: (i) a shelterwood where 80,100 mature Scots pine trees per hectare remained after cutting and (ii) a clearcut where no trees were left. 2,On average, 3741 m2 per hectare of root bark was present in the humus layer, of which 135 m2 was not coniferous but comprised species such as bilberry and broadleaved trees. 3,The mean area debarked by pine weevils was 2.9 m2 per hectare; 2.6 m2 of conifer roots and 0.3 m2 of bilberry roots. Roots of broadleaved trees were almost never consumed. No clear preferences for roots of a specific level of vitality were observed. 4,No consistent difference between the shelterwood and clearcut was found, either in the amount of root bark area available or in the extent of root feeding by pine weevil. 5,A weak negative correlation between debarked areas on roots and seedlings was found, indicating that root feeding may have reduced damage to seedlings. 6,It is concluded that conifer roots in the humus layer constitute a major food source for the pine weevil and can be utilized for a considerable period in both clearcuts and shelterwoods. [source]


    Sub-lethal responses of the large pine weevil, Hylobius abietis, to the pyrethroid insecticide lambda-cyhalothrin

    PHYSIOLOGICAL ENTOMOLOGY, Issue 4 2006
    D. ROSE
    Abstract The response of the large pine weevil (Hylobius abietis) to the pesticide lambda-cyhalothrin, a pyrethroid, is investigated. Both behavioural (feeding preferences) and nutritional and physiological (lipid content) responses are recorded. Hylobius abietis shows both a significant avoidance of pesticide-treated food sources and a decrease in lipid content after exposure, but a full recovery after feeding on untreated food. It is proposed that the mechanism for the pesticide avoidance and altered lipid levels is due to an anti-feedant effect of the pesticide. Implications for pest management programmes are described. [source]


    Feeding on roots in the humus layer by adult pine weevil, Hylobius abietis

    AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2006
    Kristina Wallertz
    Abstract 1,The consumption by adult pine weevil, Hylobius abietis, of the bark of roots present in the humus layer was assessed in a field study conducted in southern Sweden during two years (1998 and 2002). The study sites were divided into two areas: (i) a shelterwood where 80,100 mature Scots pine trees per hectare remained after cutting and (ii) a clearcut where no trees were left. 2,On average, 3741 m2 per hectare of root bark was present in the humus layer, of which 135 m2 was not coniferous but comprised species such as bilberry and broadleaved trees. 3,The mean area debarked by pine weevils was 2.9 m2 per hectare; 2.6 m2 of conifer roots and 0.3 m2 of bilberry roots. Roots of broadleaved trees were almost never consumed. No clear preferences for roots of a specific level of vitality were observed. 4,No consistent difference between the shelterwood and clearcut was found, either in the amount of root bark area available or in the extent of root feeding by pine weevil. 5,A weak negative correlation between debarked areas on roots and seedlings was found, indicating that root feeding may have reduced damage to seedlings. 6,It is concluded that conifer roots in the humus layer constitute a major food source for the pine weevil and can be utilized for a considerable period in both clearcuts and shelterwoods. [source]


    Feeding by the pine weevil Hylobius abietis in relation to sun exposure and distance to forest edges

    AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2003
    Göran Nordlander
    Abstract, 1,The intensity of feeding by adult pine weevils Hylobius abietis (L.) on the stem bark of Norway spruce Picea abies (L.) Karst. seedlings planted in rows with a north,south orientation across a clear-cutting, was measured throughout a growth season. The feeding was then correlated to light interception, soil temperature and distance to the nearest forest edge. 2,Feeding was at least twice as intense on seedlings in the central part of the clear-cutting compared to those at the edges. The decline began approximatety 15 m from the edge and was of similar proportions on both the sun-exposed and shaded sides. 3,Measures of global radiation and soil temperature correlated well with consumption on the shaded side. However, on the sun-exposed side, there were no apparent correlations with global radiation or soil temperature that could explain the decline in consumed bark area. 4,We conclude that the decline in feeding towards the forest edges was mainly due to factors other than the microclimate variables we monitored. We suggest that the presence of roots of living trees along the forest edge may reduce damage to seedlings, since they provide an alternative source of food for the weevils. This alternative-food hypothesis may also explain why seedlings in shelterwoods usually suffer less damage from pine weevils than seedlings in clear-cuttings. [source]