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ŠUMARSKI LIST 1-2/2014 str. 22     <-- 22 -->        PDF

that they described I. cembrae but they actually described I. subelongatus (Terasaki et al. 1987, Yamaguchi et al. 1989, Zhang et al. 1992, Suzuki and Imada 1993, van der Westhuizen et al. 1995, Yamaoka et al. 1998, Zhang et al. 2000).
The main host for I. cembrae throughout the area of its distribution, from the lowest altitudes to the subalpine zone, is the European larch (Larix decidua Mill.) (Postner 1974). The beetle occasionally colonizes Norway spruce (Picea abies (L.) Karsten) (Pfeffer 1989). An infestation on Swiss pine (Pinus cembra L.) reported by Eichhoff (1871) was revised by Pfeffer (1995), who determined that Ips amitinus had been incorrectly identified as I. cembrae.
Ips cembrae is generally considered a secondary pest in larch plantations (Grégoire and Evans 2004), breeding in logs (Elsner 1997), wind-blown trunks (Krehan and Steyer 2005), and storm-damaged (Luitjes 1974) and dying trees (Grodzki 2008) (Figure 1). Drought conditions at drier sites may promote the infestation of green trees (Bevan 1987). In such cases, I. cembrae breeds and subsequently acts as a primary pest on healthy trees and can threaten young and old stands in lower and medium altitudes (Grodzki and Kosibowicz 2009). I. cembrae can also damage apparently healthy larch trees when it increases to large numbers, in which case defoliation can result from maturation feeding by young beetles on thin twigs in the crowns or from regeneration feeding of older beetles in thin trunks or thicker branches (Postner 1974, Krehan and Cech 2004).
Ips cembrae is considered a serious pest in some European countries (Grégoire and Evans 2004). Short-term outbreaks were triggered in central Europe by extreme drought in 2003 (Krehan and Cech 2004, Knížek and Zahradník 2004, Stratmann 2004). In Poland, its breeding was promoted by wood left by the thinning of young larch forests (Hutka 2006). While wood infested by I. cembrae peaked in the Czech Republic in 2006 and then declined, the quantity of wood damaged by bark beetles in Poland increased six-fold between 2006 and 2007 (Grodzki and Kosibowicz 2009). Outbreaks are known from the past, e.g., I. cembrae occur­red on spruce following a Lymantria monacha (Linné, 1758) outbreak during the 1920s in central Europe (Pfeffer 1955).