A method for trapping hylobius abietis (L.) with a standardized bait and its potential for forecasting seedling damage

A method for trapping walking Hylobius abietis (L.) (Coleoptera: Curculionidae) was developed and evaluated. Synergism between α‐pinene and ethanol in attracting H. abietis was confirmed. The effects of varying release rates of these substances and of adding other host terpenes were studied. A simple bait was developed containing α‐pinene and ethanol released from separate vials. The correlation between trap catch and seedling damage was estimated during May, June, and August on 1‐, 2‐, and 3‐year‐old clear‐cuttings. In May and June, population levels were relatively high on all clear‐cuttings and no significant correlations were found. The August experiment showed a strong positive correlation between catch and damage. The percentage damaged seedlings per captured weevil was considerably higher in August than in May or June. Possibilities for developing a system for forecasting seedling damage using this trapping method are discussed.     

黄山风景区松材线虫病危险性评估 Ⅰ.松蛀虫种类、种群分布及动态监测

报道了黄山风景区松蛀虫种类、主要松蛀虫成虫活动期、种间种群数量比率和种内种群数量垂直分布比率 ,2 0 0 1年 5种松蛀虫成虫种群数量变动规律、不同监测期松墨天牛雌成虫孕卵量及比率。研究结果表明 ,黄山风景区繁衍着 14种松蛀虫 ,主要松蛀虫有 5种 :马尾松角胫象、松墨天牛、短角幽天牛、褐幽天牛、松树皮象。其种群数量比率分别为 6 1.6 %、2 7.0 %、5 .5 %、3.8%和 2 .2 %。松墨天牛成虫最高分布区为海拔 16 5 8m的天海景点 ,海拔 318m的白亭景点种群数量分布比率最高 ,达80 .9% ,诱获的松墨天牛雌成虫平均孕卵量为 2 5 .3粒     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.